The main parts of a proof are the statements and the reasons. The statements are things you want to prove, and the reasons are the justifications for the statements. Some parts of a proof will provide a given statement or a visual with some congruency.
I hope this helps!
~kaikers
Answer:
Area of big rectangle - area of mini rectangle
56in2 - 3in2
B. 53 in2
2 / 5 = 12 / 30
2 / 6 = 10 / 30
12 + 10 = 22
22 / 30 = 11 / 15
4 + 5 = 9
9 and 11 / 15 is your answer
You have the intercepts and x-coordinate of the vertex correct. There appears to be a math error in the calculation of the y-value of the vertex.
f(7/8) = (4*7/8 -7)*(7/8) -15 = -49/16 -15 = -289/16 = -18.0625