Step 1:
x² + 4x = 192
Step 2:
Take x common:
x ( x + 4) = 192
Length is x and width is x+4
Step 3:
x² + 4x - 192 = 0
Step 4:
x² + 16x - 12x - 192 = 0
x(x+16) - 12(x+16) = 0
(x-12)(x+16) = 0
⇒ x=12, x=-16
Because the length can't be -16, the length is 12.
Answer:
30 yards per minute.
Step-by-step explanation:
Unit rate is basically when the denominator is 1. In this case, 450 is divisible by 15, so if you divide that, you get 30.