Solve the following system of equations by elimination

Mathematics

1 answer:

olya-2409 [2.1K]2 years ago

5 0

Answer:

y = -6

x = 1

Step-by-step explanation:

-x + 2y = -13

-x - 2y = 11

Sum the equations:

-x -x = -2x

+2y - 2y = 0

-13 + 11 = -2

then

-2x = -2

x = -2/-2

x = 1

from the first eq.

-x + 2y = -13

-1 + 2y = -13

2y = -13 + 1

2y = -12

y = -12/2

y = -6

check:

from the second eq.

-x -2y = 11

-1 -(2*-6) = 11

-1 -(-12) = 11

-1 + 12 = 11

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