Question

Solve. 5x2 – 20 = 0

x = 5 and x = 4

x = 4 and x = 2

x = –5 and x = 20

x = 2 and x = –2

Answer 1

\( \color{Black}{\Rightarrow 5(x^2 - 4) = 0}\)

Divide both sides by 5.
\( \color{Black}{\Rightarrow x^2 - 4 = 0 }\)

Now factor \(x^2 - 4\).

Answer 2

5x^2-20=0 you can factor 5 out so we do that like this
5(x^2-4) = 0
5(x - 2 )(x + 2 ) = 0
x - 2 = 0 add 2 to each side to isolate x
x=2
and for the other one
x + 2 = 0
subtract two from each side to isolate x

x= -2

therefore, x=2,-2