Question 828039
4y-x=5+2y   3x+7y=24 use 

rewrite  4y-x=5+2y
subtract 2y from each side
2y-x=5
-x+2y=5
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So we now have 
-x+2y=5
3x+7y=24 
multiply the top equation by 3
-3x+6y=15
3x+7y=24 
add the equations
13y=39
divide each side by 13
 y = 3
substitute 3 for y in -x+2y=5
-x+2(3)=5
-x+6=5
add -6 to each side
-x = -1
x = 1
substitute 1 for x and 3 for y in the original equations
4y-x=5+2y
4(3)-1?=5+2(3)
12-1?=5+6
11=11
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3x+7y=24
3(1)+7(3)?=24
3+21?=24
24=24