SOLUTION: solve this linear equation by elimination and substitution and work must be shown. 2x-4y=-4 and 4x+5y=48. Thanks

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Question 315131: solve this linear equation by elimination and substitution and work must be shown.
2x-4y=-4 and 4x+5y=48.
Thanks
Answer by malaydassharma(59) About Me  (Show Source):
You can put this solution on YOUR website!
Elimination Method:
2x-4y=-4 ..(i)
4x+5y=48 ..(ii)
Multiplying (i) by 2
4x-8y=-8 ..(i)
4x+5y=48 ..(ii)
subtracting (i) - (ii) we get
-13y=-56
y=56 / 13


2x-4y=-4 ..(i)
4x+5y=48 ..(ii)
Multiplying (i) by 5 and (ii) by 4

10x-20y=-20 ..(i)
16x+20y=192 ..(ii)
Adding (i) + (ii) we get
26x=172
x=172/26= 86/13
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Substitution Method:
Solved by pluggable solver: SOLVE linear system by SUBSTITUTION
Solve:
+system%28+%0D%0A++++2%5Cx+%2B+-4%5Cy+=+-4%2C%0D%0A++++4%5Cx+%2B+5%5Cy+=+48+%29%0D%0A++We'll use substitution. After moving -4*y to the right, we get:
2%2Ax+=+-4+-+-4%2Ay, or x+=+-4%2F2+-+-4%2Ay%2F2. Substitute that
into another equation:
4%2A%28-4%2F2+-+-4%2Ay%2F2%29+%2B+5%5Cy+=+48 and simplify: So, we know that y=4.30769230769231. Since x+=+-4%2F2+-+-4%2Ay%2F2, x=6.61538461538462.

Answer: system%28+x=6.61538461538462%2C+y=4.30769230769231+%29.