SOLUTION: Hi, Marcos had 15 coins in nickels and quarters. He had 3 more quarters than nickels. He wrote a system of equations to represent this situation, letting x be the number of nickel

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Question 422961: Hi,
Marcos had 15 coins in nickels and quarters. He had 3 more quarters than nickels. He wrote a system of equations to represent this situation, letting x be the number of nickels and y represent the number of quarters. Then he solved the system by graphing. What is the solution?
A)(6,9)
B) (5,10)
Thanks for you help, been really appreciated

Found 2 solutions by jim_thompson5910, stanbon:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
"Marcos had 15 coins in nickels and quarters" means that x%2By=15

"He had 3 more quarters than nickels" means that y=x%2B3


Graph the two equations to get



Graph of x%2By=15 (red) and y=x%2B3 (green)


We can see that they intersect at the point (6,9). So the solution is choice A)


Notice that 6+9 = 15 and 9 = 6 + 3


If you need more help, email me at jim_thompson5910@hotmail.com

Also, please consider visiting my website: http://www.freewebs.com/jimthompson5910/home.html and making a donation. Thank you

Jim

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Marcos had 15 coins in nickels and quarters.
n + q = 15
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He had 3 more quarters than nickels.
q = n + 3
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He wrote a system of equations to represent this situation, letting n be the number of nickels and q represent the number of quarters. Then he solved the system by graphing. What is the solution?
graph%28400%2C300%2C-10%2C10%2C-10%2C10%2C15-x%2Cx%2B3%29
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Ans: A
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Cheers,
Stan H.
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A)(6,9)
B) (5,10)