Use a double-angle or half-angle identity to find the exact value of each expression?

Answer:

B

Step-by-step explanation:

each of the numbers is just adding 1.25 on to it

Answer: Choice B

16.00, 17.25, 18.50, 19.75, ...

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Explanation:

We start with $16.00 as the first term, as this is the amount the boss pays him initially. Then we add on 1.25 to get 16+1.25 = 17.25 to represent the next wage after that first raise.

Then after the second raise he gets, he'll then earn 17.25+1.25 = 18.50 an hour. This process theoretically can go on forever, but realistically the boss will likely set some kind of limit.

We say that this sequence { 16.00, 17.25, 18.50, 19.75, ... } is arithmetic with the first term of 16.00 and common difference 1.25

The common difference is the gap width between any two neighboring terms, and it's the amount the wage goes up each time he gets a raise.

Answer:

How can postulates and theorems relating to similar and congruent triangles be used to write a proof? If the three sets of corresponding sides of two triangles are in proportion, the triangles are similar. ... If the three sets of corresponding sides of two triangles are in proportion, the triangles are similar.

Step-by-step explanation:

Hope this helps :D good luck!!

Answer:

C.47,5cm²

Step-by-step explanation:

Answer:

25%

Step-by-step explanation:

let the MP be x

sp without vat =x-16%of x

= 21x/25

sp with VAT = 21x/25 +13% of 21x/25

rs 9492 = 2373x/2500

( 9492*2500)/2373=x

x = 10000

cp = ((21x/25 )*100)/100+5 ( 5= profit percent )

=8000

(10000-8000)×100%/8000

=25%

[tex]\\ \sf\longmapsto f(2+h)[/tex]

[tex]\\ \sf\longmapsto 4(2+h)-3[/tex]

[tex]\\ \sf\longmapsto 4h+8-3[/tex]

[tex]\\ \sf\longmapsto 4h+5[/tex]

Answer:

Step-by-step explanation:

Well I can show you by example. Try 28

a = 2

b = 8

2 - 2*8 = 2 - 16 = -14

- 14 is divisible by 7. You get - 2.

That means that 28 is also divisible by 8

We'll try one more. Try 56

a = 5

b = 6

5 - 2*6 = 5 - 12 = - 7

- 7 is divisible by 7 so 56 must be as well. What I'm wondering is if the rule in some form works for 735 and if it does how?

a = 73

b = 5

73 - 10 = 63

63 is divisible by 7 (giving 9)

so 10*73 + b is divisible by 7.

Try something a bit harder.

115444

a = 11544

b = 4

a - 2*4

11544 - 8

11536 / 7

1648 which works perfectly.

115444 is divisible by 28 which is a multiple of 7

Really amazing! Thanks for posting.

Answer:

a union b= {1,2,3,4,5}

a intersection b ={2,3}

Step-by-step explanation:

The union of two sets A and B is a set that contains all the elements of A and B and is denoted by A U B

the set composed of all elements that belong to both A and B is A intersection B (A ∩ B)

Answer:

20×2=40bnmcsshjvghjpiutewqadgjlmbcz

Answer: all real numbers

Step-by-step explanation:

Answer:

0.7

Step-by-step explanation:

7/11 = 0.63636363

7/9 = 0.777777778

so a decimal between them will be, 7/10 = 0.7

Answer:

they are in order cross x with the y across from it

Step-by-step explanation:

Answer:

[tex]\frac{y}{2}[/tex]

Step-by-step explanation:

n is doubled: 2n

y added: 2n + y

divided by 2: n + [tex]\frac{y}{2}[/tex]

n subtracted -> final resutl: [tex]\frac{y}{2}[/tex]

Answer:

A, E or 1, 5

Step-by-step explanation:

Its not A, D

Answer:

B

Step-by-step explanation:

n is the number of litres.

if you substitute 1 for 'n' then you will get :

C = 8 + 1.5(1)

C = $9.5

$9.50 for every litre

Answer:

C is correct

Step-by-step explanation:

The $8 charge is only once regardless of how many liters are ordered, so only answer C works.

Answer:

easy

Step-by-step explanation:

4ab³6a²b

Answer:

[tex] \frac{12 {a}^{2} {b}^{3} 6 {a}^{2}b }{3ab} \\ thank \: you[/tex]

Answer:

(x + 5)(x + 5)

Step-by-step explanation:

[tex]x^2+10x+25\\(x+5)(x+5)[/tex]

Answer:

(x+5)(x+5)

Step-by-step explanation:

x²+10x+25

x²+5x+5x+25    

x(x+5)+5(x+5)            

(x+5)(x+5)

Answer:

All of them except 12:25 simply to 2:5. So 12:25 is the odd one out.

Answer:

Hello

Step-by-step explanation:

[tex]y=2x^2-12x+19\\=2(x^2-6x)+19\\=2(x^2-2*3*x+9)+19-18\\=2(x-3)^2+1\\\\Vertex\ is\ (3,1)\\\\Axis\ of\ symmetry\ is\ x=3\\\\y-intercept\ is \\\\y=2(0-3)^2+1=19\\[/tex]

Answer:

let,

√x-5=ky

x=30 when y=2

√30-5=2k

or, k=(√30-5)/2

now, when y=8

√x-5=8×(√30-5)/2

or, √x-5=4√30-20

or, √x=4√30-15

or, x=(4√30-15)²

or, x=47.73..

Answer:

there is a 25% decrease in books being read

Answer:

Step-by-step explanation:

[tex]f(x)=\frac{x+9}{7-4x} \\put ~f(x)=y\\flip~x~and~y\\f(y)=x\\y=f^{-1}(x)\\y=\frac{x+9}{7-4x} \\flip~x~and~y\\x=\frac{y+9}{7-4y} \\x(7-4y)=y+9\\7x-4xy=y+9\\-4xy-y=9-7x\\or\\4xy+y=7x-9\\y(4x+1)=7x-9\\y=\frac{7x-9}{4x+1} \\or~f^{-1}(x)=\frac{7x-9}{4x+1}[/tex]

Answer:

DE = 11

Step-by-step explanation:

DF = DF +EF

4x+2 = x+7 + 7

Combine like terms

4x+2 = x+14

Subtract x from each side

4x+2-x = x+14-x

3x+2 = 14

Subtract 2 from each side

3x+2-2 =14-2

3x=12

Divide by 3

3x/3 = 12/3

x = 4

DE = x+7 = 4+7 =11

Answer:

DE is 11

Step-by-step explanation:

[tex]DE = DF - EF \\ DE = (4x + 2) - 7 \\DE = 4x - 5 [/tex]

But for x:

[tex]4x + 2 = (x + 7) + 7 \\ 4x + 2 = x + 14 \\ 3x = 12 \\ x = 4[/tex]

Therefore:

[tex]DE = (4 \times 4) - 5 \\ = 16 - 5 \\ = 11[/tex]

Answer:

Step-by-step explanation:

I am not sure what your first inequality is saying y≤2x +7 or y≥2x+7

-the equation y> -3x-2 , has a negative slope m= -3 (the line is going down from left to right if is a negative slope) and it has to be a dotted line( <, or > is a dotted line, ≤, or ≥ is a solid line) so the answer must be either A or D

-if the second equation is y≤2x +7 then the answer is D because y has to be less than 2x+7 the area under the line will be include in the solution

--if the second equation is y≤2x +7 then the answer is A because y has to be greater than 2x+7 the area above the line will be include in the solution

Answer:

1 4/5

Step-by-step explanation:

2x+7>-3x-2

2x+3x>-2-7

5x/5>-9/5

=1 4/5

Thanks Hope It Help

Answer:

Step-by-step explanation:

I can't believe I'm doing this for 5 points, but ok!

For the first 3, we are going to multiply to find the value of that 3 x 3 matrix by picking up the first 2 columns and plopping them down at the end and then multiplying through using the rules for multiplying matrices:

[tex]\left[\begin{array}{ccccc}7&4&6&7&4\\-4&8&9&-4&8\\1&8&7&1&8\end{array}\right][/tex]  and from there find the sum of the products of the main axes minus the sum of the products of the minor axes, as follows (I'm not going to state the process in the next 2 problems, so make sure you follow it here. This is called the determinate. The determinate is what you get when you evaluate or find the value of a matrix. Just so you know):

[tex](7*8*7)+(4*9*1)+(6*-4*8)-[(1*8*6)+(8*9*7)+(7*-4*4)][/tex] which gives us:

392 + 36 - 192 - [48 + 504 - 112] which simplifies to

236 - 440 which is -204

On to the second one:

[tex]\left[\begin{array}{ccccc}-8&-4&-1&-8&-4\\1&7&-3&1&7\\8&9&9&8&9\end{array}\right][/tex] and multiplying gives us

[tex](-8*7*9)+(-4*-3*8)+(-1*1*9)-[(8*7*-1)+(9*-3*-8)+(9*1*-4)][/tex] which gives us:

-504 + 96 - 9 - [-56 + 216 - 36] which simplifies to

-417 - 124 which is -541, choice c.

Now for the third one:

[tex]\left[\begin{array}{ccccc}-2&-2&-5&-2&-2\\2&7&-3&2&7\\8&9&9&8&9\end{array}\right][/tex] and multiplying gives us

[tex](-2*7*9)+(-2*-3*8)+(-5*2*9)-[(8*7*-5)+(9*-3*-2)+(9*2*-2)][/tex] which gives us:

[tex]-126+48-90-[-280+54-36][/tex] which simplifies to

-168 - (-262) which is 94, choice c again.

Now for the last one. I'll show you the set up for the matrix equation; I solved it using the inverse matrix. So I'll also show you the inverse and how I found it.

[tex]\left[\begin{array}{cc}-4&-5&\\-6&-8\\\end{array}\right][/tex] [tex]\left[\begin{array}{c}x\\y\\\end{array}\right][/tex] = [tex]\left[\begin{array}{c}-5\\-2\\\end{array}\right][/tex] and I found the inverse of the 2 x 2 matrix on the left.

Find the inverse by:

* finding the determinate

* putting the determinate under a 1

* multiply that by the "mixed up matrix (you'll see...)

First things first, the determinate:

|A| = (-4*-8) - (-6*-5) which simplifies to

|A| = 32 - 30 so

|A| = 2; now put that under a 1 and multiply it by the mixed up matrix. The mixed up matrix is shown in the next step:

[tex]\frac{1}{2}\left[\begin{array}{cc}-8&5\\6&-4\end{array}\right][/tex]  (to get the mixed up matrix, swap the positions of the numbers on the main axis and then change the signs of the numbers on the minor axis). Now we multiply in the 1/2 to get the inverse:

[tex]\left[\begin{array}{cc}-4&\frac{5}{2}\\3&-2\\\end{array}\right][/tex] Multiply that inverse by both sides of the equation. This inverse "undoes" the matrix that's already there (like dividing the matrix that's already there by itself) which leaves us with just the matrix of x and y. Multiply the inverse matrix by the solution matrix:

[tex]\left[\begin{array}{c}x&y\end{array}\right] =\left[\begin{array}{cc}-4&\frac{5}{2} \\3&-2\end{array}\right] *\left[\begin{array}{c}-5&-2\\\end{array}\right][/tex] and that right side multiplies out to

x = 20 - 5 which is

x = 15 and

y = -15 + 4 which is

y = -11

(It works, I checked it)

Answer:

11.2 cm

Step-by-step explanation:

Given that;

Arc Length Formula (if θ is in radians): l = ϴ × r

ϴ = angle subtended in radians

r= radius of the circle

l = 8cm × 1.4 radians

l= 11.2 cm

composite numbers less than 12={1,3,4,6,8,9,10}

Answer:

[tex] {(x - y)}^{2} \\ = (x - y)(x - y)[/tex]

open the brackets:

[tex] = ( {x}^{2} - xy - xy + {y}^{2} ) \\ = {x}^{2} - 2xy + {y}^{2} [/tex]