The area of a rectangle is 300 square centimeters. if the sides of the rectangle are given as 5 centimeters and centimeters, then find the value of x and the other side of the rectangle.

x is 1000, and the other side of the rectangle is 60 cm.
Area is found by multiplying length by width.  Using the sides we know we have

We divide both sides by 5:

To "undo" a square root, we square both sides:

Subtract 2600 from both sides:
3600-2600=x+2600-2600
1000=x
Now we substitute this into the side with x:

The answer is b: step 2.