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2 years ago

what is the sum of two numbers is "-7." Two times the first number equals 4 the second number. Find the two numbers.

Mathematics

1 answer:

skelet666 [1.2K]2 years ago

4 0

Answer:

$\sf \text{The numbers are $\dfrac{-14}{3} $ and $\dfrac{-7}{3}$}$

Step-by-step explanation:

Let the numbers be x , y

Sum of two numers = -7

x + y = -7------------(I)

Two times the first number equals 4 the second number.

2x = 4y ----------(II)

Divide both sides by 2

$\sf \dfrac{2x}{2}=\dfrac{4y}{2}$

x = 2y

Subtitute x = 2y in equation (I)

2y + y = -7

3y = -7

y = -7/3

Plugin y = -7/3 in equation (II)

$\sf 2x = 4*\dfrac{-7}{3}\\\\2x = \dfrac{-28}{3}\\\\x =\dfrac{-28}{3*2}\\\\x = \dfrac{-14}{3}$

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3 years ago

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2 years ago

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Answer:

Step-by-step explanation:

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So the system of equations we want to solve is:

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