The width of a rectangle is twice its length. If the perimeter is at most 72 cm, what is the greatest possible value for its length?

I need to write an algebraic equation for this and then solve it. I don't want the answer, I want to know how to make the equation.

Question

The width of a rectangle is twice its length.  If the perimeter is at most 72 cm, what is the greatest possible value for its length?

I need to write an algebraic equation for this and then solve it. I don't want the answer, I want to know how to make the equation.

anonymous · Answer

more likely that length is twice its width

anonymous · Answer

Probably, but that's what the question is saying :?

anonymous · Answer

let width =x the l = 2x
so 2(2x) + 2x <= 72
6x  <= 72

anonymous · Answer

Ohhhhhhhh! I get it! Thanks!!!

anonymous · Answer

yw

anonymous · Answer

length will be = 2x

anonymous · Answer

so is this right? 4x + 2x ≤ 72
6x ≤ 72
6x/6 ≤ 72/6
x ≤ 12

anonymous · Answer

right

anonymous · Answer

so that means that the width is 12 right? And that means that the length is 12

anonymous · Answer

no by definition length is 2 * width  
we defined x as the width
so the length is <= 24

the author of question got his width and length mixed up!

anonymous · Answer

oohh, I actually meant that the width was 6 but either way I was wrong. I see now!
Yea, but that's what makes us humans :P

anonymous · Answer

:D

anonymous · Answer

Thanks again!

anonymous · Answer

no problem