Question

I need help with algebra 2 pleasee

Answer 1

`x=\pm √(21)/7`

Explanation:

We can add 9 to both sides of the equation to get
`21x^2=9`.

We can divide both sides of the equation by 21 to get
`x^2=9/21`.

We take the square root of both sides of the equation to get
`x=\pm √(9/21)`.

However, that isn't in the form we need.

We know that
`√(9/21)=√(9)/√(21)=3/√(21)=3√(21)/(√(21)*√(21))=3√(21)/21=√(21)/7`

so the answer is really
`x=\pm √(21)/7` and we're done!