SOLUTION: by substitution, find the value of x and y if x+y =9 and 5x-2y =4

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Question 1158719: by substitution, find the value of x and y if x+y =9 and 5x-2y =4
Found 2 solutions by Alan3354, MathTherapy:
Answer by Alan3354(69443) (Show Source):
You can put this solution on YOUR website!
x + y =9
5x-2y =4
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Multiply the 1st eqn by 2, then add the 2nd eqn.
That eliminates y.
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Ooooh, substitution.
I missed that.

Answer by MathTherapy(10552) (Show Source):
You can put this solution on YOUR website!
by substitution, find the value of x and y if x+y =9 and 5x-2y =4

x + y = 9 ------ eq (i)
5x - 2y = 4 ----- eq (ii)
1) Solve eq (i) for either x or y.
2) Substitute value of solved variable in 1) into eq (ii) and solve for the NUMERICAL value of the variable NOT SOLVED for in 1).
3) Substitute NUMERICAL value for solved variable in 2) into any of the 2 equations to get the NUMERICAL value of the other!
That's it!!