SOLUTION: t...ex Problem #10 Solve the system by addition. Be sure to state the solution. 5x - 7y = 5 x + 3y = 1 Problem #11 Slove the system by graphing. Be sure to state the so

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Question 78074: t...ex
Problem #10
Solve the system by addition. Be sure to state the solution.
5x - 7y = 5
x + 3y = 1
Problem #11
Slove the system by graphing. Be sure to state the solution.
2x - 2y = 10
x + y = 3
x = 4
Answer by checkley75(3666) (Show Source):
You can put this solution on YOUR website!
5X-7Y=5 NOW MULTIPLY THE SECOND EQUATUION BY -5 & ADD
-5X-15Y=-5
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-22Y=0
Y=0 ANSWER. NOW SUBSTITUTE 0 FOR Y & SOLVE FOR X
5X=-7*0=5
5X=5
X=5/5
X=1 ANSWER.
PROOF
1+3*0=1
1=1
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2x-2y=10, -2y=-2x-10, -y=-2x/2-10/2, y=x-5
x+y=3, y=-x+3
(graph 300x200 pixels, x from -6 to 5, y from -10 to 10, of TWO functions y = x -5 and y = -x +3).
CAN'T GRAPH THE X=4 EQUATION BT IF YOU DRAW A LINE FOR X=4. -----------------------------------------------------------------
YES - YOU ARE CORRECT. i MISTAKENLY DROPPED THE - FROM THE (-2Y=-2X-10) EQUATION.
THE CORRECT GRAPH IS INCLUDED.
SORRY.