Sienna is solving a quadratic equation. She wants to find the value of x by taking the square root of both sides of the equation. Which equation allows her to do this?

Step-by-step explanation:

For Sienna to be able to take the square root of both sides while solving a quadratic equation, she must have an expression with square on at least, the side that contains the variable she is trying to determine. Equation of the form:

(x + a) ² = b

'a' and 'b' could be any number, -1, 0, 1/3, -5/6, anything really.

So, she can take square roots of both sides then, like this

√(x + a)² = √b

x + a = ±√b

x = -a ± √b

Square roots always cancel out squares, and the '±' is because a square is satisfies by both + and -, 3² = 9, and (-3)² = 9.

It is the nature of the problem being solved that determines if we take just one or both of these answers.