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Seven times a number plus three times another number equals negitive one. The sum of the tro numbers is negitive three. What are the numbers?

1 Answer

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The numbers are -5 and 2

Step-by-step explanation:

let the 1st number = x

second number = y

Seven times a number plus three times another number equals negitive one:

7 × x + 3 × y = -1

7x + 3y = -1

The sum of the two numbers is negitive three:

x + y = -3

7x + 3y = -1 ....equation 1

x + y = -3 .....equation 2

using elimination method:

multiply equation 2 by 7:

7x + 7y = -21

7x + 3y = -1

7x + 7y = -21

subtract equation 1 from 2:

7x - 7x + 7y - 3y = -21 -(-1)

4y = -20

y = -20/4

y = -5

substitute the value of y in equation 2:

x + (-5) = -3

x - 5 = -3

x = -3 + 5

x = 2

The numbers are -5 and 2

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