SOLUTION: Solve each system by elimination. 1) 10x - 8y = 16 20x - y = 2 2) -2x + 5y = 29 -2x + 2y = 20

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Question 1008285: Solve each system by elimination.
1) 10x - 8y = 16
20x - y = 2
2) -2x + 5y = 29
-2x + 2y = 20


Found 2 solutions by stanbon, ikleyn:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Solve each system by elimination.
1) 10x - 8y = 16
20x - y = 2
---
Modify for elimination::
20x - 16y = 2*16
20x - y = 2
---
Subtract and solve for "y":
15y = -30
y = -2
---
Solve for "x"::
10x = 8y + 16
10x = -16 + 16
x = 0
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2) -2x + 5y = 29
-2x + 2y = 20
----
Subract and solve for "y"::
3y = 9
y = 3
Solve for "x":
2x = 5y-29
2x = 15-29
2x = -14
x = -7
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Cheers,
Stan H.
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Answer by ikleyn(52794) About Me  (Show Source):
You can put this solution on YOUR website!
.
Solve each system by elimination.
1) 10x - 8y = 16
20x - y = 2
2) -2x + 5y = 29
-2x + 2y = 20
-----------------------------------------
1) 
10x - 8y = 16  (1)
20x - y = 2    (2)

Multiply the equation (1) by 2 (both sides) and then distract it from (2). In this way you eliminate y 
and get one single equation for x:

-y - (-16)y = 2 - 32,

15y = -30,

y = -30%2F15 = -2.

Then find x from (2): 20x = y + 2 = -2 + 2 = 0, x = 0. 



2)
-2x + 5y = 29   (1)
-2x + 2y = 20   (2)

Distract (2) from (1) and do the rest yourself.