# SOLUTION: Solve the system by substitution. 2x + 4y = 10 y = 2x + 15

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 Click here to see ALL problems on Graphs Question 28155: Solve the system by substitution. 2x + 4y = 10 y = 2x + 15 Answer by sdmmadam@yahoo.com(530)   (Show Source): You can put this solution on YOUR website!Solve the system by substitution. 2x + 4y = 10 ----(1) y = 2x + 15 ----(2) Putting (2) in (1) (that is substituting for y) Then (1) becomes 2x + 4(2x+15) = 10 2x +(8x +60) = 10 (2x+8x) =10-60 [By additive associativity and adding (-60) to both the sides] 10x = -50 x = (-50)/10 = -5 Putting x=-5 in (2), y = 2x +15 becomes y = 2X(-5) +15 = -10 + 15 = +5 Answer: x = -5 and y = 5 Verification: putting x = -5 and y = 5 in (1) LHS = 2x + 4y = 2X(-5)+ 4X(5) = -10+20 = 10 =RHS Therefore our answer is correct.