How do you solve #4x^2 -18=82# graphically and algebraically?

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Answer 1 · 2017-09-11T07:50:06

By arranging the original equation

Your equation can be written
#4x^2 = 82+18#

#4x^2 = 100#

#x^2=100/4#

#x^2=25#

The solution for x is #x=5# and #x=-5# (there are two values).

Graphically the solution is provided below

#y=x^2 - 25#
When y is zero, you can find x (-5 and +5)

graph{(x^2)-25 [-10, 10, -30, 20]}