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2 votes
Solve
7x+5y=40
2x+4y=-4
by elimination

User Lasandra
by
8.2k points

1 Answer

1 vote
Step 1 solve for one variable

2x = -4 - 4y

x = -2 - 2y

Step 2 eliminate by substituting into second equation and solve

2 * (-2-2y) + 5y = 40

-4 - 4y + 5y = 40

y = 36

Step 3 put y into any original equation

7x + 5*36 = 40

7x + 180 = 40

7x = -140

x = -20

So

X = -20 and Y = 36
User Brankica
by
7.3k points