Question 954558
We can assign the variable {{{x}}} and {{{y}}} to the length and width of the rectangle. In this case, I will assign {{{x}}} to the length and {{{y}}} to the width of the rectangle. As the length is three times its width, the equation would be:
{{{x=3y}}}.
Finding the perimeter of a rectangle is always the sum of two times the length and two times the width. {{{P}}} stands for perimeter in this equation. That is:
{{{P=2x+2y}}}.
In the first equation, we already have {{{x}}} isolated, we can plug it in to the second equation. We know that the perimeter is 30, so we can also plug that in for {{{P}}}.
{{{30=2(3y)+2y}}}.
Simplifying us would give us
{{{30=6y+2y}}}
{{{30=8y}}}.
{{{y=3.75}}}
So now we know that the width of the rectangle is 3.75.
We can now plug this back in to the original equation to get:
{{{x=3(3.75)}}}
{{{x=11.25}}}.
So the answer is Length=11.25 and Width=3.75.