Question

Find the width of the rectangle if the length of the rectangle is 5 more than it’s width, and the perimeter of the rectangle is 20 units

Answer 1

Answer:width 6 units

Step-by-step explanation:

if width=x and length= 5+x

therefore........20=2(x+x+5)

                     20=4x+10

                      x=20-4+10

                     x=6 units

width=6 units

Answer 2

Answer:

w = 2.5

Step-by-step explanation:

Write these 2 equations to represent the problem:

$l=w+5\\2w+2l=20$

Then this can be solved as a system of equations here. I'll solve by substitution, and as the $l$ is already solved for at the top:

$2w+2l=20\\2w+2(w+5)=20\\2w+2w+10=20\\4w+10=20\\4w=10\\w=2.5$

If you just need the width, then you're already done there. I'll find  the other variable too, and then check it to be sure it's correct.

$l=w+5\\l=(2.5)+5\\l=7.5$

Now, confirm that with the second equation:

$2w+2l=20\\2(2.5)+2(7.5)=20\\5+15=20\\20=20$