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Seven times a number plus three times another number equals -1 the sum of two numbers is -3 what are the numbers?

User David Boho
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1 Answer

6 votes

Answer:

7x + 3y = - 1

x + y = - 3

Find what y (Or x, but make sure you find the same variable for both equations) is:

3y = - 7x - 1

y = - 7/3x - 1/3

y = - x - 3

Substitute:

- 7/3x - 1/3 = - x - 3

Solve for x (Or y, depending on which one you used):

4/3x = 2 2/3

x = 2

Plug x (Or y) into one of the equations:

2 + y = - 3

y = - 5

Answer: x = 2, y = -5

User Patrick Pirzer
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