the perimeter of a rectangle equals the sum of the lengths of its four sides. If the width of a rectangle is 3 inches and its perimeter is 36 inches, find the length of the rectangle

Question

anonymous · Answer

@Jhannybean @zzr0ck3r @Isaiah.Feynman

jhannybean · Answer

|dw:1376437955176:dw| The perimeter of a rectangle is fund by the equation $\large P = 2l +2w$ where $l$ = length and $w$ = width. Were given $w=3$ but not the length, so we labeled it an unknown variable. We're alsogiven the length of the perimeter, $P= 36 \ in$ Now we plug this all into the equation. $$\large 36 = 2x +2(3)$$ We're going to be solving for the length, therefore we need to isolate the x on one side of the equation. $$\large 36 - 6 = 2x$$$$\large x = \frac{30}{2}$$  Can you solve for x?

anonymous · Answer

15 @Jhannybean

jhannybean · Answer

Yes, good job. :)

jhannybean · Answer

So the length = 15 = x. We can also check to make sure the length and width gives us 36. $$\large 36 = 2(3) + 2(15)$$$$\large 36 = 6 + 30$$$$\large 36 = 36 \ \checkmark $$