How do you solve x^2+10x+9=0x2+10x+9=0 using the quadratic formula?

1 Answer
Oct 25, 2014

The quadratic formula is

x = (-b +- root 2 (b^2 - 4ac))/(2a)x=b±2b24ac2a

where aa, bb, and cc are the coefficients of the terms of the quadratic equation

For your equation we have

x^2 + 10x + 9 = 0x2+10x+9=0

=> x = (-10 +- root 2 (10^2 - 4(1)(9)))/(2(1))x=10±21024(1)(9)2(1)

=> x = (-10 +- root 2 (100 - 36))/(2)x=10±2100362

=> x = (-10 +- root 2 64) / 2x=10±2642

=> x = (-10 +- 8)/2x=10±82

=> x = (-10 + 8)/2, x = (-10 - 8)/2x=10+82,x=1082

=> x = -1, x = -9x=1,x=9