Question

Molly is designing a dog house for her puppy that has a rectangular base.  The length of the base is 

7 inches  more than its width.  She wants the area of the base to be at least  375 square inches.

If  w  represents the width of the doghouse, write the inequality that can be used to determine the possible dimensions of the base of the dog house.

1 A. 375 B. -1 C. -7 D. 382 E. 7

2 A. 7 B. 375 C. 1 D. -7 E. 382

3 A. > B. < C. =

4 A. 7 B. -7 C. 1 D. 375 E. 382

Answer 1

Let us denote with w the width of the doghouse, and with l the length.
We know that the length of the base is 7 inches more than its width. So, we can write: l=w+7
Area of a rectangle can be calculated with the formula:
area=width*length
In our case, the are of the doghouse is:
area=l*w=(w+7)*w=w^2+7w
Molly wants the area of the base to be at least 375 square inches, so we can write:
w^2+7w≥375