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Question 72128: Solve the system of equations using the substitution method.
If the answer is a unique solution, present it as an ordered pair: (x, y). If not, specify whether the answer is “no solution” or “infinitely many solutions.”
-4x + y = 8
2x + 3y = -1
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I tried doing it but got a really long decimal.
-4x + y = 8
2x + 3y = -1
Y= 4x+8
2x + 3(4x+8) = -1
2x+ 12x +24 = -1
14x + 24 -24 = -1 – 24
14x= -25
x= 1.785714286
Answer by ankor@dixie-net.com(22740)   (Show Source):
You can put this solution on YOUR website! f the answer is a unique solution, present it as an ordered pair: (x, y). If not, specify whether the answer is “no solution” or “infinitely many solutions.”
-4x + y = 8
2x + 3y = -1
--------------------------------------------------------------------------------
I tried doing it but got a really long decimal.
-4x + y = 8
2x + 3y = -1
Y= 4x+8
2x + 3(4x+8) = -1
2x+ 12x +24 = -1
14x + 24 -24 = -1 – 24
14x= -25
x= 1.785714286
:
Everything you did is right, except it should be -1.7857...
:
To find y:
2(-25/14) + 3y = -1
-50/14 + 3y = -1
3y = -1 + 50/14
3y = -1 + 3.5714; using decimals
3y = +2.5714
y = 2.5714/3
y = +.857 another annoying decimal
:
Check both solutions in the 1st equation
-4x + y = 8
-4(-1.7857) + (.857) =
+7.1428 + .857 = 7.9998 ~ 8
:
You know what you're doing, they're just trying to intimidate you
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