Ben C. answered • 05/12/15

Medical Student and Researcher for Math and Science Tutuoring

If √(x - 3.4 - 15) = 5, what is the value of x?

You have a couple of options to start this question. First you can either get rid of the square root by exponentiating everything by 2 on each side (raising everything to the second power), or you can simplify the mess under the square root a bit. First let's get rid of the square root and then everything will look more like regular algebra.

(√(x - 3.4 - 15))

^{2}= (5)^{2}So solving on each side, on the left the square root is cancelled out by squaring and on the right 5

^{2}= 5*5 = 25x - 3.4 - 15 = 25

So now that everything looks much more friendly, it should be easy to solve.

Add 15 to both sides to get rid of the 15 on the left:

x - 3.4 -15 + 15 = 25 +15

x - 3.4 = 40

Now add 3.4 to both sides to get rid of the 3.4 you are subtracting from x on the left:

x - 3.4 + 3.4 = 40 + 3.4

Note that positive and negative 3.4 on the left cancel out:

x - 3.4 + 3.4 = 40 + 3.4

Now add 3.4 to 40 and you have found x!

x = 40 +3.4

x = 43.4