Question

The length of a rectangle is 5x its width. If the area of a rectangle is 320 yd^2, what is its perimeter?

Answer 1

this seems so easy... but im just spacing how to even make an equation out of this..

Answer 2

320 = lw
320 (5w) w ?

Answer 3

lets say the width is 'x'. Then the length is 5x since it is "5 times the width". The area of this rectangle would then be (Legth)(Width) = (5x)(x) :\[5x^{2}\]
Setting this equal to the area of the rectangle (320 square yds) gives us:
\[5x^{2}=320 \Rightarrow x^{2} = 64 \Rightarrow x = \pm 8\]
but you cant have a "length" of negative 8, so x is 8.
This means the width is 8 yrds, and the length is 5(8) = 40 yrds.
The perimeter is 2(l + w) = 2(40+8) = 2(48) = 96 yrds

Answer 4

ok! thanks!!!