How do you solve x^2 + 5x + 3 = 9x2+5x+3=9?

1 Answer
Jul 2, 2018

x = -6, x = 1x=6,x=1

Explanation:

Given: x^2 + 5x + 3 = 9x2+5x+3=9

Solve means to find the values of xx that make the equation true.

Put the equation in the form: Ax^2 + Bx + C = 0Ax2+Bx+C=0 by subtraction 99 from both sides of the equation:

x^2 + 5x -6 = 0x2+5x6=0

Factor the equation by finding two numbers that multiply to

ul(A*C = -6 " and sum to " B = 5)
-2 * 3 = -6 " "-2+3 = 1" doesn't work"
-6 * 1 = -6 " "-6 + 1 = -5" doesn't work"
6 * -1 = -6 " " 6 + -1 = 5" works"

x^2 + 5x -6 = 0 => " "(x+6)(x-1) = 0

x + 6 = 0; " " x - 1 = 0

x = -6, x = 1