math word problem

Question

The length of the top of a table is
5m greater than the width. The area is 84m²
Find the dimensions of the table.

Answer 1

Hi Amy, 

Step One: Create Let Statements

Let w=width

Let length=5+w

Step Two: Write our equation

84m²=w(5+w)

84=5w+w²

0=w2+5w-84

(w+12)(w-7)

w=-12 w=7

(since we cannot have a negative length, we discard the w=-12)

∴The length is 12m and the width is 7m

Best, 

Starlyte

Answer 2

A=l*w

length=w+5

84=w(w+5)

84=w^2+5w

w^2+5w-84=0

factor

84=2*2*3*7=(2*2*3)*(7) and 12-7=5

(w+12)(w-7)=0

w-7=0

w=7 m

l=12 m