length and width/algebra

classic Classic list List threaded Threaded
3 messages Options
pretty1 pretty1
Reply | Threaded
Open this post in threaded view
|

length and width/algebra

The length of a rectangle is 9 yards more than the width, If the perimeter is 138 yards, what are the length and the width?
AlgebraHouse AlgebraHouse
Reply | Threaded
Open this post in threaded view
|

Re: length and width/algebra

I've done hundreds of these.

w = width
w + 9 = length   {length is 9 more than the width}

Perimeter of a rectangle = 2(width) + 2(length}

2w + 2(w + 9) = 138   {substituted width and length into perimeter formula}
2w + 2w + 18 = 138   {used distributive property}
4w + 18 = 138   {combined like terms}
4w = 120   {subtracted 18 from each side}
w = 30   {divided each side by 4}
width is 30 yards

length = w + 9
= 30 + 9   {substituted 30, in for w, into w + 9}
= 39   {added}
length is 39 yards

- Algebra House
pretty1 pretty1
Reply | Threaded
Open this post in threaded view
|

Re: length and width/algebra

thank you