7. A plot of land for sale has a width of $x \mathrm{ft}$., and a length that is $8 \mathrm{ft}$ less than its width. $A$ farmer will only purchase the land if it measures 240 square feet. What value of $x$ will cause the farmer to purchase the land?
8. The length of a rectangle is 5 inches more than twice a number. The width is 4 inches less than the same number. If the area of the rectangle is 15 , find the number
Answer
\(\boxed{5}\) is the number for the second problem.
Step 1 ：For the first problem, set up the equation: \(x(x - 8) = 240\)
Step 2 ：Solve for x: \(x = 20\)
Step 3 ：\(\boxed{20}\) ft is the width that will cause the farmer to purchase the land.
Step 4 ：For the second problem, set up the equation: \((n - 4)(2n + 5) = 15\)
Step 5 ：Solve for n: \(n = 5\)
Step 6 ：\(\boxed{5}\) is the number for the second problem.
