What is the vertex form of #y = 12x^2 - 6x + 8#?

1 Answer
Nov 30, 2015

#y = 12(x + frac(1)(4))^2 + frac(29)(4)#

Explanation:

You can get this equation into vertex form by completing the square

First, factor out the coefficient of the largest power of x:
#y = 12(x^2 - frac(1)(2)x) + 8#

then take half of the coefficient of the x to the first power and square it
#frac(1)(2) * frac(1)(2) = frac(1)(4) rightarrow frac(1)(4)^2 = frac(1)(16)#

add and subtract the number you just found within the parenthesis
#y = 12(x^2 + frac(1)(2)x + frac(1)(16) - frac(1)(16)) + 8#

take the negative #frac(1)(16)# out of the parenthesis
#y = 12(x^2 + frac(1)(2)x + frac(1)(16)) - frac(3)(4) + 8#

factor and simplify
#y = 12(x + frac(1)(4))^2 + frac(29)(4)# #leftarrow# answer