Question

A store is having a sale on trail mix and jelly beans. For 2 pounds of trail mix and 3 pounds of jelly beans, the total cost is $12 . For 6 pounds of trail mix and 5 pounds of jelly beans, the total cost is $30 . Find the cost for each pound of trail mix and each pound of jelly beans.

Answer 1

let the cost of a pound of trail mix be x
and the cost of a pound of jelly bean be y
2x +3y = 12
and
6x+5y = 30

Answer 2

i get y = -2/3x+12

Answer 3

y= -6/5x+30

Answer 4

hint: you don't necessarily have to solve for y

Answer 5

so whats the answer :o ?

Answer 6

I think the process of elimination would work better

Answer 7

how do you do process of elimination on this ?

Answer 8

let x be a pound of trail mix and let y be a pound of jelly beans.
2x+3y=12
6x+5y=30

Let's do substitution. Isolate x in the first equation.
2x= 12-3y
x=6-3/2 y.
Substitute that into the second equation.
6(6-3/2y)+5y=30.
36-18/2 y+5y=30
-9y+5y=-6
-4y=6
y=1.5

Put that back into the first equation
2x=12-3(1.5)
2x=7.5
x=3.75
So the trail mix is $3.75 and the jellybeans are $1.50

Answer 9

1. 2x +3y = 12
2. 6x+5y = 30

multiply 1. by -3 to eliminate the x

-6x -9y = -36
6x +5y = 30

Answer 10

Then you add these two equations together.

(-9 +5)y = -36+30
-4y = -6
y = 6/4 = 3/2

Answer 11

oh okay i get it now !!

Answer 12

Then you use y = 3/2 into any one of the two equations to find x.

2x + 3(3/2) = 12

2x + 9/2 = 12

2x = 12 - 9/2

2x = 15/2

x = (15/2)/2 = 15/4