How do you solve 4x^2-6=-12x?

1 Answer
Dec 27, 2016

x=(-3+-sqrt(15))/2

Explanation:

4x^2-6=12x

rarr 4x^2+12x-6=0

rarr 2x^2+6x-3=0

applying the quadratic formula:
color(white)("XXX")x=(-6+-sqrt(6^2-4 * 2 * (-3)))/(2 * 2)

color(white)("XXX")=(-6+-sqrt(36+24))/4

color(white)("XXX")=(-cancel(6)^3+-cancel(2)sqrt(15))/(cancel(4)_2)

You could use a calculator if you needed this in an approximate decimal form:
color(white)("XXX")(-3+-sqrt(15))/2~~0.43691673 or -3.436491673