Question

Find the product of (x+10) (x-10)

Answer 1

Answer:

$x^{2} - 100$

Step-by-step explanation:

There are 2 ways to do this, both producing the same answer (obviously)

1. one of the most common patterns in quadratics is the difference of 2 squares (which is this). By seeing this, you automatically know the product is gonna be the first term squared minus the second term squared:

$x^{2} -10^{2}= x^{2} -100$

2. The other method is to use FOIL, which means u multiply the first terms, then the first and the second, then the second and the first, then the second terms. Like this:

(x + 10)(x - 10)

= (x*x) - (x*10) + (10*x) - (10*10)          this simplifies to:

$x^{2} +0 - 100\\= x^{2} -100$

i hope this helps!