Question

You will need 100 feet of fencing to put all the way around a rectangular garden. The length of the garden is 30 feet. What is the width?
1. 3,000 feet
2. 20 feet
3. 30 feet
4. 40 feet

PLS HELP!! ♥

Answer 1

Because you need 100 feet of fencing to go all the way around, the circumference of the rectangle is 100.

Then, because this is a rectangle, both sides of the length are equal and both sides of the width are equal.

Therefore, we can represent the circumference with the following equation:
100=2(30)+2x, where x is the width.

Then we solve for x be rearranging the equation.
First simplify:
100=60+2x
Then subtract 60 from both sides
40=2x
Then divide both sides by 2
20=x

Therefore, the width of the garden is 20 feet.