Question

How do you solve `10x^2 = 250`?

Answer 1

You can begin by dividing both sides by `10`. This is allways allowed in an equation.

Explanation:

Now you have `x^2=25`, or
"find the number that will give `25` when squared"

You would be tempted to take the square root:
`x=sqrt25=5`, but that is only half the answer, because:
`5^2=25` but also `(-5)^2=25`

In questions like this, always look for the negative root.