Because they make 4 dollars for every book sold, a representative equation would be:
Answer:
The cosine of the angle is 4/5.
Step-by-step explanation:
An acute angle is between 0º and 90º, in the first quadrant of the trigonometric circle, in which both the sine and the cosine are positive values.
For each angle
, we have that:

We have that:

So




The cosine of the angle is 4/5.
Converting decimals into fractions is simple, all you have to do is think about the number, for example .25, if you look at it you realize it's 1/4 of 1, so it's naturally 1/4, you do this with all of them
I would find the area of the shape as if it were a rectangle (5x9) and then subtract the area of two triangles (1/2x2x2.5)