Question

factirize ( x2 - 4x - 21)​

Answer 1

Answer:

Quadratic equations whose roots are integers can be solved by factoring. To factor, find two numbers whose sum is 4 (the coefficient of the middle term) and whose product is -21 (the constant term).

...

Solving a Quadratic Equation By Factoring.

x2 + 4x - 21 = 0 x2 + 4x - 21 = 0

0 = 0 0 = 0

So, the roots are 3 and -7