7(2+5v)=3v+14
14+35v=3v+14
-3v -3v
14+32v=14
-14 -14
32v=0
÷32 ÷32
v=0
hope this helps!!
Linda should use ...
15 gallons of 80% juice
5 gallons of 60% juice
_____
Let g represent the number of gallons of 80% juice needed. Then (20-g) is the number of gallons of 60% juice Linda will use. The amount of juice in the mixture can be written as
0.80g +0.60(20 -g) = 0.75×20
0.20g = 20(0.75 -0.60) = 20×0.15
g = 20×0.15/0.20 = 15
The amount of 80% juice needed is 15 gallons, so 5 gallons of 60% juice are needed.
