posted by M
You have some quarters and some nickels in your pocket in total you have 7 coins and together they are worth 95 cents how many nickels and how many are quarters?
I know the equations will have something to do with the 7 couns and they are worth 95 cents all together
Is one of them x+y=95
I know that there will be 3 quarters and 4 nickels because 3 quarters is 75cents and 4 more nickels equals 95, but how would I make 2 equations for the problem.
Actually one of them is x+y=7
that counts the coins. Now you have to count the value.
If you have x nickels and y quarters, then
5x+25y = 95
Now, you can insert your first equation into this one as follows:
5x+5y+20y = 95
5(x+y)+20y = 95
5(7)+20y = 95
35+20y = 95
20y = 60
That is how to arrive at the solution algebraically, rather than just guessing.
There are also other ways to manipulate the equations, but this one seemed quite natural to me.