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3 years ago

I need help I don’t understand and I need to show my work who would help me??

Mathematics

2 answers:

stich3 [128]3 years ago

5 0

Answer: b

Step-by-step explanation:

In the last question, you wrote on a second equation "13x ...." kkk

Let's go:

We have to check each one answer in the following system:

x - 2y = 7

3x + 7y = 8

I can use the substituition method to solve this system...

x = 7 + 2y

3x + 7y = 8

3(7 + 2y) + 7y = 8

21 + 6y + 7y = 8

13y = 8 - 21

13y = -13

y = -1

x = 7 + 2.(-1)

x = 5

Finally, the correct answer is the second one (letter b).

Gre4nikov [31]3 years ago

4 0

The answer is B! I hope this helps. Enjoy the holidays

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