Four times a number less 7 is equal to 12 more than two times that number

Answer:

D

Step-by-step explanation:

Note that I will be using a, b, and y instead of their Greek counterparts.

First, we know that sin(c+d) = sin(c)cos(d) + cos(d)sin(a) and sin(c-d) = sin(c)cos(d) - cos(d)sin(a). We can apply these here to get

sin(b+y) = sin(b)cos(y) + cos(b)sin(y)

sin(b-y) = sin(b)cos(y) - cos(b)sin(y)

sin(a+y) = sin(a)cos(y) + cos(a)sin(y)

sin(a-y) = sin(a)cos(y) - cos(a)sin(y)

Plugging these into our equation, we get

(sin(b)cos(y) + cos(b)sin(y) - (sin(b)cos(y) - cos(b)sin(y)))

/

(sin(a)cos(y) + cos(a)sin(y)-(sin(a)cos(y) - cos(a)sin(y)))

=

2cos(b)sin(y) / 2cos(a)sin(y)

= cos(b)sin(y)/cos(a)sin(y)

= cos(b)/cos(a)

Next, we can see that a+b = π, so we can subtract b from both sides to get a = π -b. Plugging that in for a in our equation, we get

cos(b) / cos(π-b)

After that, we know that cos(c-d) = cos(c)cos(d) - sin(c)sin(d). Plugging that in here, we get

cos(π-b) = cos(π)cos(b) - sin(π)sin(b)

= -cos(b) + 0

= -cos(b)

Plugging that back into our equation, we get

cos(b) / -cos(b) = -1

Answer:

(2/3)n + 7

Step-by-step explanation:

Represent the number by n.

Then "two thirds of (that) number" is (2/3)n.

Finally, we add 7:

"Two-thirds of a number increased by seven" is (2/3)n + 7

Answer:

B=(.31, .95)

Step-by-step explanation:

When your at the point (1,0) you are at 0 degrees (cos 0, sen 0) = (1,0).

So at 72 degrees you moved 72 degrees (cos 72, sin 72) = (.31, .95)

Answer:

58%

Step-by-step explanation:

10*5=50

7*3=21

21/50 chance to choose inside small rectangle

21/50*2 = 42/100 chance to choose inside small rectangle

100-42=58%

Answer:

17) 250 km²

18) never

19) sometimes

20) 288 in³

Step-by-step explanation:

17)

this polygon can be seen as the combination of two shapes : a 16×13 rectangle on top, and a right-angled triangle at the bottom.

this triangle has the side lengths

15 km

(16 - 10) = 6 km

(27 - 13) = 14 km

the total area is the area of the rectangle plus the area of the triangle.

the area of the rectangle (length×width)

Ar = 16×13 = 208 km²

the area of the triangle (baseline×height/2)

since it is a right-angled triangle, we use one side of the 90 degree angle as baseline and the other as height

At = 6×14/2 = 3×14 = 42 km²

so the total area of the polygon

Ap = Ar + At = 208 + 42 = 250 km²

18) the first quadrant is the area between the right (positive) side of the x axis and the upper (positive) part of the y axis. all points here have always and only positive x and y values. never any negative ones.

19) when a point is on the x-axis, well, left of point 0 on the x -axis are only negative values of x. and right of point 0 of the x-axis are only positive values of x. so, for some of these points the x value is positive, and for some it is negative. therefore "sometimes".

20) the volume of a box is length×width×height.

V = 8×3×12 = 24×12 = 288 in³

The ratio of the number of students who went to the zoo to the number of students who did not go to the zoo is 1: 5. Hence option C is true.

Given that;

The students in Shawn's class got to choose whether to visit the zoo or the aquarium.

Here, 3 students went to the zoo and 15 students went to the aquarium.

Hence, the ratio of the number of students who went to the zoo to the number of students who did not go to the zoo is,

Ratio = 3 : 15

Ratio = 3/15

Ratio = 1/5

Ratio = 1 : 5

Thus, option C is true.

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Answer:

The correlation coefficient is approximately -0.9949

Step-by-step explanation:

The given data is presented as follows;

[tex]\begin{array}{lcl}x&&y\\-10&&2\\-8&&-3\\-1&&-15\\-4&&-10\\-6&&-6\\-7&&-5\\-5&&-8\\-3&&-13\\-2&&-14\\-9&&-1\end{array}[/tex]

The correlation coefficient, r is given as follows;

[tex]r = \dfrac{\sum(x_i - \overline x) \cdot (y_i - \overline y)}{\sqrt{\sum (x_i- \overline x)^2\times \sum (y_i- \overline y)^2 } }[/tex]

From MS Excel, we have;

∑([tex]x_i - \overline x[/tex])·([tex]y_i - \overline y[/tex]) = -155.5

∑([tex]x_i - \overline x[/tex])² = 82.5

∑([tex]y_i - \overline y[/tex])² = 296.1

Therefore, r = -155.5/(√(82.5 × 296.1)) ≈ -0.9949

The correlation coefficient, r ≈ -0.9949

Answer:

3.6

Step-by-step explanation:

the ratio of AB to AD is 3/5 so the ratio of BC to DE is also 3/5, therefore BC=3/5 DE= (3/5)6= 3.6

Answer:

44.4

Step-by-step explanation:

Since we have a right triangle, we can use trig functions

sin theta = opp / hyp

sin x = 7/10

Taking the inverse sin of each side

sin^-1 (sin x) = sin^-1(7/10)

x = 44.427

Rounding to the nearest tenth

x = 44.4

Answer

root 354

Step-by-step explanation:

Answer:

12

Step-by-step explanation:

(√19 -√7)(√19 +√7)

( a +b)( a -b) = a²-b²

(√19)² -(√7)² = 19 -7 = 12

Answer:

7

Step-by-step explanation:

10 minus 3 will give you the number

Answer:

7

Step-by-step explanation:

let the number added to 3 be 'x'

we know;

X+3=10

X=10-3

X=7

( − 2 ) ( 3+ 2 2 − − 2 )

Hope this helps, have a great day!

Answer:

142.5

Step-by-step explanation:

π×11²×135/360

= 363π/8

= 142.5 (rounded to the nearest tenth)

Answered by GAUTHMATH

Answer:

g(x) = 3·sin(x + π/2) - 4

Step-by-step explanation:

The given (general form of a) sin function is g(x) = A·sin(x + C) + D

Where;

A = The amplitude (the vertical stretch) = 3

C = The phase shift, left = π/2

D = The vertical shift = 4 units down = -4

Therefore, given that in the parent function, we have f(x) = sin(x), by substituting the values of A, C, and D to complete the equation modeling the function g, we get;

g(x) = 3·sin(x + π/2) - 4

Answer:

FED ~ MLF

Step-by-step explanation:

∠L = ∠E

∠F = ∠F

Since both angles are congruent, that would mean all angles are congruent.

If all angles are congruent, then the triangles are always similar no matter the length of the sides.

The complete statement is [tex]\triangle FED\sim \triangle FLM[/tex].

Similar triangles are the triangles that have the same shape, but their sizes may vary.

If any two angles of a triangle are equal to any two angles of another triangle, then the two triangles are similar to each other.

When two lines intersect each other, then the opposite angles are formed due to intersection are called vertical angles or vertically opposite angles.

According to the given question.

We have two triangles LMF and EDF

In triangles LMF and EFD we have

∠MLF = ∠DEF   (given)

Also, ∠MFL = ∠DFE   (vertically opposite angles)

Since, we know that " if any two angles of a triangle are equal to any two angles of another triangle, then the two triangles are similar to each other".

Therefore, by AA similarity criteria triangle FED is similar to FLM.

Hence, the complete statement is [tex]\triangle FED\sim \triangle FLM[/tex].

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Answer:

Step-by-step explanation:

This equation turns out to be a quartic. I'm not sure what should be done with. I can't believe you were asked to find its roots which are unbelievably complex. Here is a graph with the only 2 points that are easily found. If I am not solving what you need, please leave a note.

Explanation:

The gradient is the same as the slope

m = slope

m = rise/run

m = (change in y)/(change in x)

m = (y2-y1)/(x2-x1)

m = (6-1)/(6 - (-4))

m = (6-1)/(6+4)

m = 5/10

m = 1/2

In decimal form, this becomes 0.5

A slope of 1/2 means we move up 1 and to the right 2 units each time to generate points along the diagonal line.

A positive slope goes uphill as we move to the right (due to the positive rise value).

Answer:

One way to find the gradient is using the expression :

[tex]m = \frac{y_{2} - y_{1}}{x_{2} - x_{1}} = \frac{y_{B} - y_{A}}{x_{B} - x_{A}}[/tex]

So [tex]m = \frac{6 - 1}{6- (-4)} =\frac{5}{10} =\frac{1}{2}[/tex]

Answer:

The Slope-Intercept Form is essentially a special case of the Point-Slope Form. It's said that two points determine a line. That truism is used to quickly sketch a line if its equation is given in the Two Intercept-Form ax + by = c. We get the y-intercept by setting x = 0 and solving for y: by = c, y = c b .

Step-by-step explanation:

plzzz make brainlist and follow

Answer:

(0,2) and (6,0)

Step-by-step explanation:

y-intercept, x=0

0+3y=6

y=2

x-intercept, y=0

x=6

Answer:

A square shaped room contains 12m³of air.If the height of the room is 3m,what is the area of the floor. find the length too.also write the method ka answer

Step-by-step explanation:

please mark me brainlist

Answer:

Step-by-step explanation:

I think you mean 35 seconds because if it was 36 then the answer would be too long so assuming it is 35 seconds the answer is 1 minute or 60 seconds

Answer:

3(2×2+1)+3×(2×2)/3=1×3=4×3

36+3+4=3=12

36+3+4-3-12

43-15

28

Answer:

Just use m a t h w a y for the answer

Step-by-step explanation:

Thank me later,or dont thank me at all

Here, we are to find the length and the , breadth of the rectangle

The length of the rectangle = 7 units and Breadth of the rectangle = 3 units

Let

length = l units

Breadth = b units

Perimeter of the rectangle = 20 units

length is the distance measured along the longest dimension of an object

width is the wideness of an object

perimeter refers to the total measurements of an objects

The breadth of a rectangle is 4 units less than its length

If,

Length = l

Then,

b = l - 4

Perimeter of a rectangle = 2(length + breadth)

20 = 2{l + (l - 4)

20 = 2(l + l - 4)

20 = 2(2l - 4)

20 = 4l - 8

20 + 8 = 4l

28 = 4l

l = 28/4

l = 7

b = l - 4

b = 7 - 4

b = 3 units

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Answer:

3. (1-7/9)÷2 = 2/9÷2 = 1/9

reciprocal of 1/9 is 9

4. x+2/x=3

if you solve it, you get x = 1 and x = 2, so last option, 1 and 2, is the answer

Answered by GAUTHMATH

Answer:

25

Step-by-step explanation:

5 cents = 0.05

1.25 / 0.05 = 25

let me know if i'm wrong

Answer:

25

Step-by-step explanation:

$1.25=125cents

125/5 = 25

Answer:

523.33 cm³

Step-by-step explanation:

Volume of sphere is given by the formula :

V = (4/3)×pi×r³

= (4/3)×3.14×125

= 523.33 cm³

Answer:

Thanks for the points... dude.....