X = large boxes and y = small boxes
x + y = 70.....x = 70 - y
60x + 65y = 4300
60(70 - y) + 65y = 4300
4200 - 60y + 65y = 4300
5y = 4300 - 4200
5y = 100
y = 100/5
y = 20 <=== the small boxes weigh 20 lbs
x + y = 70
x + 20 = 70
x = 70 - 20
x = 50 <== and the large boxes weigh 50 lbs
The answer you are looking for is B. 15
200,000,000 + 40,000,000 + 9,000,000 + 100,000 + 4,000 + 300 + 30
You just have to plug your coordinates into the distance formula.
(1, 6) (8, 1)
(X1, Y1) (X2, Y2)
do the work and you get 8.6