How do you solve the quadratic equation by completing the square: v^2+6v-59=0v2+6v59=0?

1 Answer
Jul 23, 2015

^v^2+6v-59 =0^v2+6v59=0
color(white)("XXXX")XXXXrarrcolor(white)("XXXX")XXXXv=-3+-2sqrt(17)v=3±217
color(white)("XXXX")XXXX(by completing the square)

Explanation:

v^2+6v-59 = 0v2+6v59=0
color(white)("XXXX")XXXXMove the constant to the right side (out of the way)
v^2+6v = 59v2+6v=59
color(white)("XXXX")XXXXAdd as the third term the value needed to make the right side a square
v^2+6v+3^2 = 59+9v2+6v+32=59+9
color(white)("XXXX")XXXXRe-write right side as a squared binomial
(v+3)^2 = 68(v+3)2=68
color(white)("XXXX")XXXXTake the square root of both sides
v+3 = +-sqrt(68) = +-2sqrt(17)v+3=±68=±217
color(white)("XXXX")XXXXIsolate vv by subtracting 33 from both sides
v = -3+-2sqrt(17)v=3±217