3 years ago

Which of the following (x,y) pairs is the solution for the system of equations x+2y=4 and -2x+y=7

Mathematics

1 answer:

kakasveta [241]3 years ago

3 0

Answer:

(-2 ,3)

Step-by-step explanation:

Step 1: Rewrite first equation

x = 4 - 2y

-2x + y = 7

Step 2: Substitution

-2(4 - 2y) + y = 7

Step 3: Solve y

-8 + 4y + y = 7

-8 + 5y = 7

5y = 15

y = 3

Step 3: Plug in y to find x

x + 2(3) = 4

x + 6 = 4

x = -2

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