The length of a rectangle exceedss its width by 8 inches. The perimeter is 80 inches. Find the length and width of the rectangle
If you let the width be x units long. Then how long will the length be?
If the perimeter is 80 what will length + width be?
So would it be
Notreallymath has asked if this is correct:
No, Not quite.
If a is the width then
The the length will be a+8
This means that the perimeter will be a+a+ a+8 + a+8 = 4a+16
4a+16 = 80
But what I was getting at is that the perimeter is 2*length + 2*width
so a HALF of the perimeter is length+ width
x + x+8 = 40
2x = 32
x = 16
so the width is 16 and the length is ??
You can do it either way though.
Apply the perimeter formula for rectangle which is:
we already know that length=x+8 and width is x
2*(x+8+x)= 2*(2x+8) = 4x+16
well the perimeter as the question says is 80 inches
subtract 16 from both sides
divide by 4
Well width is x so it is 16
You can make sure by subistuting length and width in the perimeter formula
yes indeed these values work.