Question 81633: help please
Sally bought three chocolate bars and a pack of gum and paid $1.75. Jake bought two chocolate bars and four packs of gum and paid $2.00. Find the cost of a chocolate bar and the cost of a pack of gum.
Answer by weepingwillowcats(10)   (Show Source):
You can put this solution on YOUR website! First, set up your equation.
Let "c" stand for the chocolate bars and "g" stand for the gum.
Sally bought 3c and 1g and paid $1.75.
You can express this with the equation 
Do the same to find what Jake bought.
Now, you must use substitution to solve the problem.
You can choose either equation to work with.
For the sake of this problem, we'll go with the first equation.
First, solve for one of your variables.
Because it will be easier, we'll go with the variable g.
To do this, you're going to subtract 3c from either side.
Since there were not like-terms, this is as simplified as this equation can get at the moment.
Now, you will substitute the g in your second equation with this answer.
From here, you will use the distributive property.
Combine like terms.
Subtract 7 from both sides. 
Divide by -10 from each side. 
Now you know how much each chocolate bar costs.
Next, you plug in this answer back into either one of your original equations (for Sally or Jake).
I'll go with the first one, from Sally.
Simplify.
Subtract 1.5 from both sides.
So, each pack of gum costs $0.25
Chocolate Bars = $0.50
Pack of Gum = $0.25
If you want to check your answers, simply plug each number back into your equation.
Goodluck
-weepingwillowcats
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