SOLUTION: y=5x+3 y=15x+2 solved by elimination method

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Question 1158032: y=5x+3
y=15x+2
solved by elimination method

Found 2 solutions by Theo, josmiceli:
Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
y = 5x + 3
y = 15x + 2
subtract the first equation from the second to get:
0 = 10x - 1
add 1 to both sides of the equation to get:
1 = 10x
divide both sides of the equation by 10 to get:
1/10 = x
replace x with 1/10 in the first equation to get:
y = 5 * 1/10 + 3
solve for y to get:
y = 5/10 + 30/10 = 35/10
replace x with 1/10 and y with 30/10 in the second equation to get:
35/10 = 15/10 + 2
leave the left side of the equation as is and evaluate the right side of the equation to get:
35/10 = 15/10 + 20/10 = 35/10
this confirms the values of x = 1/10 and y = 35/10 are good.
your solution is:
x = 1/10 and y = 35/10

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
(1) +y+=+5x+%2B+3+
(2) +y+=+15x+%2B+2+
----------------------------
Subtract (1) from (2)
(2) +y+=+15x+%2B+2+
(1) +-y+=+-5x+-+3+
---------------------------
+0+=+10x+-+1+
Add +1+ to both sides
+1+=+10x+
Divide both sides by +10+
+x+=+1%2F10+
----------------------------------
check:
(1) +y+=+5%2A%281%2F10%29+%2B+3+
(1) +y+=+1%2F2+%2B+6%2F2+
(1) +y+=+7%2F2+
and
(2) +y+=+15%2A%281%2F10%29+%2B+2+
(2) +y+=+3%2F2+%2B+4%2F2+
(2) +y+=+7%2F2+
OK
The solution is ( 1/10, 7/10 )