SOLUTION: solve. {5x+ 2y=28 and 3x-4y=48

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Question 116332This question is from textbook
: solve.
{5x+ 2y=28 and 3x-4y=48 This question is from textbook

Answer by MathLover1(20850) About Me  (Show Source):
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solve:
5x+%2B+2y+=+28....(1).........multiply by 2
3x+-4y+=+48......(2)..
---------------
10x+%2B+4y+=+56..........add (1) and (2)
+3x+-+4y+=+48
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10x+%2B+3x+%2B+4y+-4y+=+56+%2B+48
13x+=+104
x+=+104%2F13
+x+=+8
now eather from (1) or (2) find y
10x+%2B+4y+=+56..........(1)........move 10x to the right
+4y+=+56+-+10x..........plug in x
+4y+=+56+-+10%2A8..........
+4y+=+56+-+80..........
+4y+=++-+24..........divide by 4
+y+=+-+24%2F4..........
+y+=+-+6.......................solution
check:
+x+=+8
+y+=+-+6
5x+%2B+2y+=+28....(1).........plug in x and y
5%2B8+%2B+2%28-6%29+=+28
40+-+12+=+28
28+=+28

3%2A8+-4%28-6%29+=+48......(2)..
24+%2B+24+=+48
48+=+48