Solve (x – 7)(x + 4) = 0. find x?

2 answers of x

1 Answer
Dec 18, 2017

x=-4,7

Explanation:

the only way the product of x-7 and x+4 can be 0 is if x-7 is 0, x+4 is 0, or both x-7 and x+4 are 0. otherwise, the product would be some nonzero number. this rule is the zero product property.

since x-7 and x+4 will always be different, they can't both be 0.
therefore, x-7=0 or x+4=0, so x=7 or x=-4.