-3x = 4y is the answer
Because:
-3 (-4) = 4 (-3)
-7 = -12
1- A = B = m²-16
2- D = 4x²-3 proof: (8x³-6x)/2x =2x(4x²-3)/2x simplify to get the answer
Answer: 12.19 ft
Step-by-step explanation:
Given
Length of ladder is 
Angle of elevation is 
Suppose the bottom of the ladder is x ft away from the bottom of the wall
from the figure, we can write

Thus, the distance is 12.19 ft