413,787 views
8 votes
8 votes
The width of a rectangular slab of concrete is 7 m less than the length. The area is 98 m squared. Find the dimensions

User Wunch
by
2.8k points

1 Answer

18 votes
18 votes

Answer:

Length = 14 m, Width = 7 m

Explanation:

Let the length is l and width is b.

Width, b = l-7

Area of the rectangle, A = 98 m²

We know that, the area of a rectangle is as follow :


A=lb

So,


98=l(l-7)\\\\98=l^2-7l\\\\l^2-7l-98=0\\\\l^2+7l-14l-98=0\\\\l(l+7)-14(l+7)=0\\\\l=14,-7

Length can't be negative. So,

Width, b = 14-7 = 7 m

So, the dimensions of the rectangle are 14 m and 7 m respectively.