Answer:
x = -19
Step-by-step explanation:
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.
Answer:
x= 4 y= 7 z= -6
Step-by-step explanation:
solve for one and you get them all
First, I got rid of the z by multiplying common factors (multiplied z by 2) and added equations 2 and 3 together after multiplying by 2
4x - 3y - 2z = 7
-10x+10y+2z= 18
-6x+7y= 25
Then multiplied z by -3 (to get rid of the z) with the original equation 3
3x - 2y + 3z = -20
15x-15y-3z= -27
18x-17y= -47
Next find common thing between the 2 equations we got and multiply it by that and combine (we can multiply first equation by 3 to get rid of the x and solve for y)
-18x+21y= 75
18x-17y= -47
y=7
Work backwards, substitute 7 into the above equation, you get x= 4 and then same for z to get z= -6
