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4 years ago

Can you help me solve systems of equations by elimination step by step 6x+y=15 -7x-2y=-10

Mathematics

1 answer:

Anna71 [15]4 years ago

6 0

Answer: (4, -9)

Step-by-step explanation:

Use elimination method. Manipulate one (or both) equations to eliminate one of the variables and solve for the remaining variable. I will be eliminating y

6x + y = 15 → 2(6x + y = 15) → 12x + 2y = 30

-7x - 2y = -10 → 1(-7x + 2y = -10) → -7x - 2y = -10

5x = 20

x = 4

Next, replace "x" with "4" into either equation and solve for y.

6(4) + y = 15

24 + y = 15

y = -9

Check:

Plug in x = 4 and y = -9 into the other equation to verify it makes a true statement.

-7x - 2y = -10

-7(4) - 2(-9) = -10

-28 - -18 = -10

-28 + 18 = -10

-10 = -10 $\checkmark$

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