SOLUTION: Solve using the substitution method x + 4y = 2; 6x + 5y = -12

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Question 416975: Solve using the substitution method
x + 4y = 2; 6x + 5y = -12
Found 2 solutions by MathLover1, Gogonati:
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

x+%2B+4y+=+2........1
++6x+%2B+5y+=+-12.......2
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x+%2B+4y+=+2........1..solve for x

x+=-4y+%2B2..plug it in 2

++6%28-4y+%2B2%29+%2B+5y+=+-12.......solve for y

++-24y+%2B12+%2B+5y+=+-12

++-19y+=+-12-12

++-19y+=+-24

+y+=+-24%2F-19

+y+=0.79........plug in x+=-4y+%2B2 and find x

x+=-4%28.79%29+%2B2
x+=-3.16+%2B2
x+=-1.16

check:
x+%2B+4y+=+2
-1.16+%2B+3.16+=+2
2+=+2

Answer by Gogonati(855) About Me  (Show Source):
You can put this solution on YOUR website!
Solution: From the first linear equation x=2-4y Substitute this value of x in the second equation; 6(2-4y)+5y=-12 This is a first grade equation. Solving it we find out the value of y. 12-24y +5y=-12: -19y=-24; y=24/19 To find out the x value substitute y=24/19 in the first equation; x=2-4(24/19); x=-58/19.
Answer: the solution for this system linear equations is the ordered pair (-58/19,24/19).