SOLUTION: solve the system of equations using elimination. all work must be shown please help. x+9=28 -5x+8y=19

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Question 1057037: solve the system of equations using elimination. all work must be shown please help.
x+9=28 -5x+8y=19
Found 2 solutions by rothauserc, MathTherapy:
Answer by rothauserc(4718)   (Show Source): You can put this solution on YOUR website!
1) x + 9y = 28 (Note I think you meant 9y)
:
2) -5x + 8y = 19
:
solve equation 1) for x
:
x = 28 - 9y
:
substitute for x in equation 2)
:
-5(28 - 9y) + 8y = 19
:
-140 + 45y + 8y = 19
:
53y = 159
:
y = 3
x = 28 - 9(3) = 1
:
**************************************************************
x = 1 and y = 3
:
check the answer by substituting for x and y in equation 2)
:
-5(1) + 8(3) = 19
:
-5 + 24 = 19
:
19 = 19
:
our answer checks
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:
Answer by MathTherapy(10552)   (Show Source): You can put this solution on YOUR website!

solve the system of equations using elimination. all work must be shown please help.
x+9=28 -5x+8y=19
Assuming the 9 in x + 9 = 28 is actually 9y, we get:

   x + 9y = 28 ------ eq (i)

- 5x + 8y = 19 ------ eq (ii)

All you have to do is multiply eq (i) by 5 to get a new equation: eq (iii).

Add eq (iii) to eq (ii) to ELIMINATE x and solve for y

Substitute value of y into any of the 2 original equations [eq (i) is the easier of the 2], and then solve for x.

There you go!! Nothing complex! 

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