Answer:
x2 - 4x - 21
Step-by-step explanation:
Area = (x -7 )(x +3)
= x*x - 7*x + x*3 - 7*3
=x2 - 4x - 21
Answer:
20 gallons
Step-by-step explanation:
105/15=7
7*20=140
Answer:
The twins would be 13 years old.
Step-by-step explanation:
21+21+21+13+13 = 89
x²(x - 4)(2x + 5) = 0
x² = 0 or x - 4 = 0 or 2x + 5 = 0
√x = √0 or x = 4 or 2x = -5
x = 0 x = 
Answer: 0, 4, 
Okay, it's wrong because they forgot to do -2 times 3x.
The correct answer is

-2x-8
Hope i got is correct!