88.3k views
2 votes
The width of a rectangle is the length minus 8 units. The area of the rectangle is 9 square units. What is the length, in units, of the rectangle?

User Jashan PJ
by
7.6k points

1 Answer

3 votes

Answer: The length is 9 units and the width is 1 unit

Explanation:

We can use the formula for the area of a rectangle to solve this problem. The formula is A = l * w, where A is the area, l is the length, and w is the width.

We have A = 9, and we know that w = l - 8. Substituting this into the formula, we get:

9 = l * (l - 8)

We can rearrange this to solve for l:

9 = l^2 - 8l

Adding 8l to both sides of the equation, we get:

9 + 8l = l^2

Subtracting 9 from both sides, we get:

8l = l^2 - 9

We can factor this to get:

l(l - 9) = 0

Since the product of two numbers is zero only when one of them is zero, we can set each factor equal to zero and solve:

l = 0 or l - 9 = 0

Adding 9 to both sides of the second equation, we get:

l = 9

Therefore, the length of the rectangle is 9 units.

User Jaynetics
by
7.2k points