How do you solve #x^ { 2} + 12x = - 60#?

2 Answers
May 8, 2017

Use the quadratic equation

Explanation:

First we need to add 60 to make the right-hand side 0:
#x^2+12x+60=0#
Since this quadratic equation is not factorable, we apply the quadratic equation:
#x=(-12+-sqrt(12^2-4*1*60))/(2*1)#
#x=(-12+-sqrt(-96))/2#
Since we cannot square root a negative value, we use #i# to denote #sqrt(-1)# as the imaginary number
#x=-6+-(4isqrt(6))/2#
#x=-6+-2isqrt(6)#
Therefore, our answers are #x=-6+2isqrt(6)# and #x=-6-2isqrt(6)#

May 8, 2017

#x=-6+-isqrt(-24)#

Explanation:

Give -

#x^2+12x=-60#

Let use completing the square method

#x^2+12x+36=-60+36#

#(x+6)^2=-24#

#x+6=+-isqrt(-24)#

#x=-6+-isqrt(-24)#