The x shows how they are meeting with the things to be with
6 minivans are needed to take (i think I'm real bad at math)
Let x be this number 10% of the number x is (10%)(x) → 0.1x
Then 10% of a number x, added to that number is (1.1x):
x + 0.1x = x(1+0.1) = x(1.1) = 1.1x
R2+15r+36=0 the answer is r=6