00:01
So in this problem, we're looking to find the dimensions of this rectangle.
00:04
So in other words, you're trying to find the width and the length.
00:07
Well, they told us that the width is 20 less than three times the length.
00:11
So because we don't know anything about that length, we can let l represent the length.
00:18
So now do we know that l is the length, let's represent the width in terms of l.
00:23
Well, it says it's 20 less than three times the length, which means it's three times l minus 20.
00:29
Now, we know the perimeter is 32 feet.
00:31
So remember, the formula defined perimeter is 2 times w plus 2 times l.
00:38
Well, we know what w is, is 3l minus 20.
00:42
So we can substitute that in place to w.
00:44
So we'll have 2 times 3l minus 20 plus 2 times l, and we know that the perimeter is equal to 32.
00:52
So we'll substitute that in for p.
00:54
So now we just need to solve this equation.
00:57
So first, let's distribute the 2.
00:58
So we're going to have 32 equals.
01:00
Well, 2 times 3l is 6l, and 2 times negative 20 is negative 40.
01:05
We'll bring down the 2l.
01:07
Well, we have like terms on the right hand side.
01:10
6l plus 2l is 8l, so we're left with 32 is equal to 8l minus 40...