SOLUTION: a+6b=5 a+3b=-1

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Question 633049: a+6b=5
a+3b=-1
Found 2 solutions by mananth, Maths68:
Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
1 a + 6 b = 5 .............1

1 a + 3 b = -1 .............2
Eliminate y
multiply (1)by 1
Multiply (2) by -2
1 a 6 b = 5
-2 a -6 b = 2
Add the two equations
-1 a = 7
/ -1
a = -7
plug value of x in (1)
1 a + 6 b = 5
-7 + 6 b = 5
6 b = 5 +
6 b = 12
b = 2
a=-7,b=2

Answer by Maths68(1474) About Me  (Show Source):
You can put this solution on YOUR website!
a+6b=5.............(1)
a+3b=-1............(2)
Subtract (2) from (1)
a+6b=5
-a-3b=1
--------
3b=6
3b/3=6/3
b=2
Put the value of b in (1)
a+6b=5.............(1)
a+6(2)=5
a+12=5
a=5-12
a=-7
a,b=-7,2

Check
=====
a+6b=5.............(1)
Put the value of a and b
-7+6(2)=5
-7+12=5
5=5


a+3b=-1............(2)
Put the value of a and b
-7+3(2)=-1
-7+6=-1
-1=-1