Question

Sally is having a problem with her puppy leaving the yard so she decides to build a new fence. The length of the yard is 7 feet more than 6 times the width. She needs 70 feet of fencing to do the job. Find the length of the yard.

Answer 1

The length = 6W + 7. 2L + 2W = 70. This is a system of equations. To get L by itself in the second problem, -2W from both sides to get 2L = 70 - 2W. Divide by 2 to get L = 35 - W. Now put them together. 6W +7 = 35 - W. Add W to both sides to get 7W + 7 = 35. Subtract 7 from both sides to get 7W = 28. Divide 7 to both sides to get W = 4. Now replace W with 4. 6(4) + 7 = L. 24 + 7 = 31. The length is 31. To check, do the second equation. 2(31) + 2(4) = 62 + 8 = 70. Your answer is 31.