ShmoopTube

00:02

Put this in your calculator and shmoop it.

00:05

If the square root of 25 minus x squared equals 3, then what is one possible positive value of x?

00:15

So we want to find this “x” fellow. In other words… we want to isolate it.

00:20

The side of the equation that contains x is under a square root.

00:23

We can undo this situation by squaring both sides, getting us 25 – x squared = 9.

00:31

Then, we subtract 25 from each side to further isolate x. Now we’re working with –x squared = -16.

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Both sides are negative, so we can multiply both sides by -1 to get x squared = 16.

00:46

From here, pretty simple. Take the square root of both sides, and we get 4.

00:50

But don’t forget it can be positive OR negative.

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