#6 is incorrect
it's 6 7/8
#7 is correct
Answer:
The answer is D
Step-by-step explanation:
All you have to do is distribute.
x^2(5x-4)+4(5x-4) =
5x^3-4x^2+20x-16
Let AM be the distance between point A and the right wall and AN be the distance between A and the left wall.
Δ AMB is an isosceles right triangle and Δ ANC is half of an equilateral triangle.
Length of AM = 30 m. Length of AN = 1/2 · 80 = 40 m.
The distance between the walls is:
30 m + 40 m = 70 m.