Solve ? . . .

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1 Answer
Mar 7, 2018

#x = -3# and #x=18#

Explanation:

Given: #-8x^2+120x+432 = 0#

Divide both sides by -8:

#(-8x^2+120x+432)/color(red)(-8) = 0/color(red)(-8)#

#x^2-15x-54 = 0#

Factor:

#(x+3)(x-18) = 0#

The root are where the factors are equal to 0:

#x+3=0# and #x-18=0#

Solve each factor for x:

#x = -3# and #x=18#