Question

The area of a rectangle is 300 square centimeters. If the sides of the rectangle are given as 5 centimeters and
`√(x+2600)` centimeters, then find the value of x and the other side of the rectangle.

Answer 1

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

`300=5(√(x+2600))`
We divide both sides by 5:

`(300)/(5)=(5√(x+2600))/(5) \\ \\60=√(x+2600)`
To "undo" a square root, we square both sides:

`60^2=(√(x+2600))^2 \\ \\3600=x+2600`
Subtract 2600 from both sides:
3600-2600=x+2600-2600
1000=x
Now we substitute this into the side with x:

`√(x+2600)=√(1000+2600)=√(3600)=60`