# How do you solve #x^2+21x+110=0#?

##### 3 Answers

#### Explanation:

So,

or

#### Explanation:

You can solve this both by factoring and Quadratic formula

Factoring

If you have a problem with factoring

Watch this video:

Factor the equation

Now we can say

This is a Quadratic equation (in form

Quadratic formula

Where

Now we have two solutions

#color(blue)( :.ul bar |x=-10,-11|#

(x + 10)(x + 11)

#### Explanation:

Use the new AC Method to factor trinomials (Socratic Search).

Find 2 numbers knowing sum (b = 21) and product (c = 11).

Since ac > 0, they have same sign.

Compose factor pairs of (c = 110) --> ...(5, 22)(10, 11). This sum is 21 = b. Then the numbers are 10 and 11.

Answer: y = (x + 10)(x + 11)