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]}

How do you solve 4x^2 -18=824x^2 -18=82 graphically and algebraically?