Multiply all three numbers to get 560 yards cubed :))
X+x+3x= 180
5x= 180
x= 36
3(36)= 108
Your answer is D. $108
Answer and work down below. Let me know if you have any questions
First, you factor and simplify (respectively) the numerator and denominator. Your equation becomes:

Notice, there is a (x + 7) on both the top and the bottom. Because of this, they cancel each other out. What is left is your answer: