Answers of "a" is -66, 18 pls show how to get to the answer of "a"
Answer:

Step-by-step explanation:
We know that A and B are complementary angles. So, they must add up to 90°. As an equation:

Since we know their equations, substitute:

Solve for x. Combine like terms on the left:

Subtract 9 from both sides:

Divide both sides by 9:

So, the value of x is 9.
We want to find A. So, let's use the equation for A:

Substitute 9 for x:

Add:

So, the measure of A is 17°.
Answer:
12.
Step-by-step explanation:
To find the mean of a group of data, you add up all of the numbers and divide the total by the amount of numbers there are. In this case, you have 15,11,10,11,14,10,15,10,and 12.
All of those numbers added together is 108.
108 divided by 9 numbers, or weeks, is 12.
The average, or mean, is 12.
Given:
Amount = 8700
Time = 3 years
Rate of interest = 24% per annum
To find:
The principal values.
Solution:
Formula for amount:

Where, A is amount, P is principal, r is the rate of interest and t is the number of years.
Putting
, we get




Divide both sides by 1.906624.



Therefore, the principal value is about 4563.04.
To find the surface area you will need to find the area of all 5 surfaces (faces) on the prism. On a triangular prism there are 2 triangular faces and 3 rectangular faces. All 3 rectangular faces are the same and the 2 triangular faces are also the same.
To find the area of the triangular faces, you will use the formula for finding the area of a triangle:
A = 1/2bh
1/2 x 10 x 8.7
A = 43.5 in^2
To find the area of the rectangular faces, you will use the formula for finding the area of a rectangle:
A = bh
10 x 3
A = 30 in ^2
30 + 30 + 30 + 43.5 + 43.5 = 177
The minimum amount of wrapping paper needed for the gift is 177 square inches.