The length of a rectangular yard is 5 feet longer than its width, x. The area of the yard is 104
sq ft. Use a quadratic to solve for the width.

I believe that x=8 but I just solved it in my head.

Question

The length of a rectangular yard is 5 feet longer than its width, x. The area of the yard is 104
sq ft. Use a quadratic to solve for the width.

I believe that x=8 but I just solved it in my head.

campbell_st · Answer

ok... so if the width = x then the length is x + 5

and using the formula for area

A = lw

so 

104 = x(x + 5)

when you distribute and collect like terms and set the equation to zero 

$$x^2 + 5x - 104 = 0$$

so find the factors of -104 that add to 5... hint the larger factor is positive

and your answer is correct.... with measurement you can only use the positive value. 

hope it helps

maddy1251 · Answer

Thank you so much @campbell_st ! Just wanted clarification that's all.