if l=5 and b=3 find the value of 2 (l+b)​

The depth of the mirror of the cross-section of a searchlight would be 8.33 cm if the light bub has a vertex at 3 cm and the mirror is 20 centimeters across at the origin.

A cross-section is perpendicular to the axis of the symmetry goes through the vertex of the parabola. The cross-sectional shape of the mirrored section of most searchlights or spotlights is parabolic.

Given:

a = 3

y = [tex]\frac{20}{2}[/tex] cm = 10 cm

Solution:

from the equation [tex]y^{2} = 4ax[/tex]

[tex]y^{2} = 4*3*x\\ y^{2} = 12x[/tex]

putting x, 10 cm in the equation

[tex]x=\frac{10^{2} }{12} \\\\x= \frac{100}{12} \\\\x= 8.33 cm[/tex]

thus, the depth of the mirror would be - 8.33 cm

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Answer:

B. 7y - 15

Step-by-step explanation:

Simplifying

10y + -3(y + 5) = 0

Reorder the terms:

10y + -3(5 + y) = 0

10y + (5 * -3 + y * -3) = 0

10y + (-15 + -3y) = 0

Reorder the terms:

-15 + 10y + -3y = 0

Combine like terms: 10y + -3y = 7y

-15 + 7y = 0

Solving

-15 + 7y = 0

Solving for variable 'y'.

Move all terms containing y to the left, all other terms to the right.

Add '15' to each side of the equation.

-15 + 15 + 7y = 0 + 15

Combine like terms: -15 + 15 = 0

0 + 7y = 0 + 15

7y = 0 + 15

Combine like terms: 0 + 15 = 15

7y = 15

Divide each side by '7'.

y = 2.142857143

Simplifying

y = 2.142857143

Answer:

b. 7y-15

Step-by-step explanation:

First, write out the expression

1. [tex]10y-3(y+5)[/tex]

To simplify the expression distribute the -3 to the terms within the paratheses.

2. [tex]10y-3y-15[/tex]

Then, combine like terms to simplify further. Since 10y and -3y are like terms they can be subtracted

3. [tex]7y-15[/tex]

This means that B is the correct answer.

Answer:

552

Step-by-step explanation:

I'm almost certain this is correct. Only one step is rounded.

Answer:  942 - 225*sqrt(3)

This is roughly equivalent to 552.29

The unit for the area is in square cm, or cm^2.

The two area values above are based on pi = 3.14, so they are approximations.

============================================================

Explanation:

The radius of the circle is r = 30 because OA = 30.

The full circle has area A = pi*r^2 = 3.14*30^2 = 2826 cm^2 approximately

However, we only want 120/360 = 1/3 of this full area to get the area of the pizza slice. So the area of the pizza slice is approximately (1/3)*2826 = 942 cm^2

This is not the final answer, but helps get us there.

What we just calculated was the approximate area of the entire figure: the yellow area plus the white triangle.

If we can find the area of the white triangle, and subtract it off, then we'll find just the area of the yellow region only.

-----------------------

The SAS (side angle side) area formula for a triangle is

Area = 0.5*p*q*sin(R)

where p,q are the sides and angle R is between those sides.

Here we have p = q = 30, which are sides OA and OB, and we have R = 120 degrees as the central angle.

So the area of triangle AOB is...

Area = 0.5*p*q*sin(R)

Area = 0.5*30*30*sin(120)

Area = 450*sqrt(3)/2

Area = 225*sqrt(3)

This value is exact.

-----------------------

The area of the yellow region is therefore

(area of full figure) - (area of triangle)

(942) - (225*sqrt(3))

942 - 225*sqrt(3)

This is approximate because we used pi = 3.14 as an approximation earlier.

You could then use your calculator to say

942 - 225*sqrt(3) = 552.288568

This rounds to 552.29

Answer:

Oxygen; 34.01°C

Step-by-step explanation:

The oxygen freezes first as it has a higher (warmer) freezing point. For both to freeze, the temperature must drop a further 34.01°C as:

-218.79 - (-252.8)

= 252.8 - 218.79

= 34.01

Answer:

37.5%

Step-by-step explanation:

150/450 = .375 = 37.5%

The percentage is 150 grams out of 400 grams will be 37.5%.

The quantity of anything is stated as though it were a fraction of a hundred. A quarter of 100 can be used to express the ratio. Per 100 is what the term percent signifies. The symbol '%' is used to symbolize it.

The percentage is given as,

Percentage (P) = [Initial value - Final value] / Initial value x 100

It is given that the difference between the initial and final value is 15 grams and the initial value is 400 grams.

Then the percentage is 150 grams out of 400 grams will be

P = (150 / 400) x 100

P = 0.375 x 100

P = 37.5%

Thus, the percentage is 150 grams out of 400 grams will be 37.5%.

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Answer:

Step-by-step explanation:

757 minutes = 12 hours 37 minutes

Answer:

hello,

answer C

Step-by-step explanation:

area of the rectangle=2b*b=2b²

area of the half cercle= [tex]\\\dfrac{\pi*(\frac{c}{2})^2}{2} =\dfrac{\pi*c^2}{8} \\[/tex]

Area in blue= 2b²-πc²/8

Answer:

p = 212

Step-by-step explanation:

p-83=129

Add 83 to each side

p-83+83=129+83

p =212

Answer:=212

Step-by-step explanation:

add 83 to both sides and then simplify

−83=129

p-83=129

p−83=129

−83+83=129+83

Answer:

a + b =1

Step-by-step explanation:

Write the given quadratic as x^2 – 1x – 90 = 0.  This factors into

(x - 10)(x + 9) = 0, and so the roots/solutions are {-9, 10}.

If we call -9 "a" and 10 "b," then the sum a + b is -9 + 10, or a + b =1.

Answer:

900°

Step-by-step explanation:

The sum of the interior angles of a polygon is

sum = 180° (n - 2) ← n is the number of sides

Here n = 7 , then

sum = 180° × 5 = 900°

Answer:

90

Step-by-step explanation:

To solve this problem we need to set up an expression

35x+20

35 is the cost per hour, and 20 dollars is the visit fee.

x is the amount of hours the CT can work

So if we plug in the amount for the number of hours from the problem we get

35(2)+20

Which becomes 70+20 which is 90.

Hope thsi helps!

The computer technician works for 2 hours will take total charges equal to $90 .

An equation is a mathematical statement that is made up of two expressions connected by an equal sign.

For example, 3x – 5 = 16 is an equation. Solving this equation, we get the value of the variable x as x = 7

According to the question

The computer technician charges $20 per visit plus $35 per hour.

i.e

Let hours he work = x

therefore,

Total charge of computer technician in equation = 20 +  35x  

Now,

As the computer technician works for 2 hours the cost will be

By using equation

Total charge of computer technician in dollars  = 20 + 35x  

where x = 2

so,

= 20 +  35*2  

= $90  

Hence, the computer technician works for 2 hours will take total charges equal to $90 .  

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Answer:100

Step-by-step explanation:

Given

Last year 160 new candidates submitted to work for agency

It is expected to increase by 25% that is , increase in one year should be

[tex]\Rightarrow 160+160\times 25\%\\\Rightarrow 160(1+0.25)\\\Rightarrow 160\times 1.25\\\Rightarrow 200[/tex]

200 application in the upcoming year. So, in 6 months, agency must have accepted 100 applications.

9514 1404 393

Answer:

Step-by-step explanation:

The GCF can be no larger than the difference between the numbers. That would be the first value you want to check to see if it is a factor of the numbers.

The difference is 10, which is a factor of both 40 and 50.

  GCF(40, 50) = 10

__

You can figure the GCF pairwise, as GCF(14, 56) = 14; then GCF(14, 63) = 7. Or, you can look at the smallest difference between any pair of numbers. Here, that is 63 -56 = 7, which is a factor of all three numbers.

  GCF(14, 56, 63) = 7

_____

Additional comment

Euclid's algorithm has you compute the remainder from division of the largest by the smallest. When that remainder is non-zero, it replaces the largest, and you repeat. When the remainder is zero, the smallest is the GCF.

For example, let's look at the GCF of 14 and 63.

  63/14 = 4 r 7

  14/7 = 2 r 0 . . . . . 7 is the divisor, so is the greatest common factor

Answer:

C

Step-by-step explanation:

The function C has a range of (-infinity, a] and domain [b, infinity)

Answer:

c

Step-by-step explanation:

come on ! you can literally see that in the chart.

how many parts of the gray 3/8 are covered by the gray 1/4 ?

2 parts = 2/8 are clearly covered by 1/4.

2/8 is what part of 3/8 ?

it is the same question as "2 is what part of 3" ?

is 2 a quarter (1/4) of 3 ? no, 1/4×3 = 3/4 and not 2.

is 2 one third (1/3) of 3 ? no, 1/3 of 3 = 1/3×3 = 1 and not 2.

is 2 two thirds (2/3) of 3 ? ah, 2/3 × 3 = 2. that is correct !

is 2 three quarters (3/4) of 3 ? no, 3/4×3 = 9/4 and not 2.

once you have the same denominator, you can easily compare the numerators and ignore the denominators for such problems.

Answer:

110.5 cubic inches

Step-by-step explanation:

Base is parallelogram, so area is

A = 4.7×5 = 23.5

Height(h) is 4.7, so volume is,

V = A×h

= 23.5×4.7

= 110.45 ≈ 110.5

Answered by GAUTHMATH

Answer:

this is this because of PTI

Step-by-step explanation:

pto explain it to me on Monday and Friday Saturday morning

Answer:

[tex]2x^2+5x[/tex]

[tex]=2xx+5x[/tex]

[tex]=x\left(2x+5\right)[/tex]

Hope it helps u

Answer:

The required sum is 392

Step-by-step explanation:

Given the sum as shown;

[tex]\sum \left \77} \atop {a=1}} \right. (3a^2-4)[/tex]

When n = 1

f(1) = 3(1)²-4

f(1) = 3 - 4

f(1) = - 1

When n = 2

f(2) = 3(2)²-4

f(2) = 12 - 4

f(2) = 8

When n = 3

f(3) = 3(3)²-4

f(3) = 27 - 4

f(3) = 23

When n = 4

f(4) = 3(4)²-4

f(4) = 48 - 4

f(4) = 44

When n = 5

f(5) = 3(5)²-4

f(5) = 75 - 4

f(5) = 71

When n = 6

f(6) = 3(6)²-4

f(6) = 108 - 4

f(6) = 104

When n = 7

f(7) = 3(7)²-4

f(7) = 147 - 4

f(7) = 143

Taking their sum

Sum = f(1)+f(2)+(3)+f(4)+f(5)+f(6)+f(7)

Sum = -1 + 8 + 23 + 44 + 71 + 104 + 143

Sum = 392

Hence the required sum is 392

Answer:

160= 2W + 2L ; W = L –16

2W+2L=160 ] ÷2

W+L= 80

W=L–16

____o____o___

L-60+L= 80 —> 2L= 96

L=48

W=L–16 —> w= 48-16 =32

W=32 ; L=48

I hope I helped you^_^

Answer: [tex]a=\sqrt{60}[/tex]

Step-by-step explanation:

To solve for a, we want to use Pythagorean Theorem as provided int eh problem. a and 2 are the legs while 8 is the hypotenuse.

[tex]a^2+2^2=8^2[/tex]           [exponent]

[tex]a^2+4=64[/tex]            [subtract both sides by 4]

[tex]a^2=60[/tex]                  [square root both sides]

[tex]a=\sqrt{60}[/tex]

Now we know that [tex]a=\sqrt{60}[/tex].

Answer:

D

Step-by-step explanation:

The quotient of n and 8 is [tex]\frac{n}{8}[/tex] and 13 more than this is

[tex]\frac{n}{8}[/tex] + 13 → D

On the last option, since you can substitute y=3x+1 into the other equations to solve for x.

Answer:

x = 0

Step-by-step explanation:

-2(2 − 2x) = 4 − 8(1 − x)

Apply the distributive property:

−2(2 − 2x) = 4 − 8(1 − x)

(−2)(2) + (−2)(−2x) = 4 + (−8)(1) + (−8)(−x)

−4 + 4x = 4 + (−8) + 8x

Combine like terms:

4x − 4 = (8x) + (4+−8)

4x − 4 = 8x + (−4)

4x − 4 = 8x − 4

Subtract 8x from both sides:

4x − 4 − 8x = 8x − 4 − 8x

−4x − 4 = −4

Add 4 to both sides:

−4x − 4 + 4= −4 + 4

−4x = 0

Divide both sides by -4:

-4x/-4 = 0/-4

x = 0

Answer: 0

Step-by-step explanation:

Answer:

A, it's the only one with a number greater then 1

Answer:

49•5

Step-by-step explanation:

A= hb×b÷2

given

hb=height=9

b=base=11

The area of the triangle will be 49.5 square units. Then the correct option is A.

Assume 'h' is the height of the triangle and 'b' be the base of the triangle. Then the area of the triangle is given as,

A = (1/2) × h·b

The height of the triangle is 9 units and the base of the triangle is 11 units. Then the area of the triangle is calculated as,

A = 1/2 x 11 x 9

A = 11 x 4.5

A = 49.5 square units

The area of the triangle will be 49.5 square units. Then the correct option is A.

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Answer:

x^2-3x

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Step-by-step explanation:

4x(x+2)-x(3x+5)

4x^2+8x-3x^2-5x

x^2-3x