SOLUTION: Hi tutor, This is a problem I'm having trouble with. 7x-4y=17 2x-2y=8 The directions is solve by elimination by addition or subtraction. Please help!

Algebra ->  Graphs -> SOLUTION: Hi tutor, This is a problem I'm having trouble with. 7x-4y=17 2x-2y=8 The directions is solve by elimination by addition or subtraction. Please help!      Log On


   

Question 193902This question is from textbook Basic Technical Mathematics
: Hi tutor,
This is a problem I'm having trouble with.
7x-4y=17
2x-2y=8
The directions is solve by elimination by addition or subtraction. Please help! This question is from textbook Basic Technical Mathematics

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
7x+-+4y+=+17
2x+-+2y+=+8
Multiply both sides of the 2nd equation by -2
7x+-+4y+=+17
-4x+%2B+4y+=+-16
Add the equations
3x+=+1
x+=+1%2F3
Substitute this result in 2nd equation
2%2A%281%2F3%29+-+2y+=+8
Multiply both sides by 3
2+-+6y+=+24
-6y+=+24+-+2
6y+=+-22
y+=+-11%2F3
Check answer:
7%2A%281%2F3%29+-+4%2A%28-11%2F3%29+=+17
7%2F3+%2B+44%2F3+=+17
Multiply both sides by 3
7+%2B+44+=+51
51+=+51
You can check the 2nd equation the same way