SOLUTION: translate the problem into a pair linear equations in two variables.solve using elimination or substitution. andy has 14 coins made up of quarters and half dollars, and their to

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Question 234434: translate the problem into a pair linear equations in two variables.solve using elimination or substitution.
andy has 14 coins made up of quarters and half dollars, and their total value is $4.25.How many quarters does he have?

Answer by eggsarecool(46) About Me  (Show Source):
You can put this solution on YOUR website!
Ok so lets say that Andy has x quarters and y half dollars.
So x%2By=14
And now for the values of the coins.
0.25%2Ax%2B0.5%2Ay=4.25 Each quarter is worth 0.25 and you multiply by x, and each half dollar is worth 0.5 and you multiply by y. When you add them up you get the amount the coins are worth.
So x=14-y
Putting this into the second equation gives us.
0.25%2814-y%29%2B0.5y=4.25 Distributing the 0.25 gives us.
3.5-0.25y%2B0.5y=4.25 Combine like terms.
0.25y%2B3.5=4.25 Subtract 3.5 from both sides.
0.25y=0.75 Divide both sides by 0.25.
y=3 We now know that y=3 and we can plug this into x=14-y to gives us x=14-3=11
So y=3 and x=11