Question 319519
 I need to solve using the addition method 

3x – 2.5y = 7.1250 
2.5x – 3y = 7.3125
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Multiply each equation by 10 to get rid of coefficient decimals.
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30x - 25y = 71.250
25x - 30y = 73.125
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Multiply thru 1st by 5
Multiply thru 2nd by 6
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150x - 125y = 356.25 
150x - 180y = 438.75
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Subtract 2nd from 1st and solve for "y"
55y = -82.5
y = -1.5
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Substitute that value into one of the equations and solve for "x":
Cheers,
Stan H.