Question

The equation 2w + 5j = 60 is used to determine the number of water bottles w and the number of juice bottles j that can be bought for $60. If you purchase 4 bottles of juice, how many bottles of water can you buy?

Answer 1

20 water bottles because 5×4=20 so 60-20=40 so you divide 40 by 2 to get 20

Answer 2

2w+5j=60
2w+5(4)+60
2w+20=60
subtract 20 from both sides
2w=40
divide 2 from both sides
w=20
check
2(20)+5(4)=60
40+20=60
60=60
so if j=4 then w=20