How do you solve the following system?: $-x -2y =-1, 3x -y = -4$

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How do you solve the following system?: $-x -2y =-1, 3x -y = -4$

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Answer 1 · 2018-03-02T00:36:29

The point of intersection is $(-1,1)$ .

Explanation:

Solve system:

$color(blue)("Equation 1:"$ $-x-2y=-1$

$color(green)("Equation 2:"$ $3x-y=-4$

The given equations are linear equation in standard form. I will show how to solve this system of equations using substitution. The resulting point $(x,y)$ is the point of intersection between the lines.

Solve Equation 1 for $x$ .

$-x-2y=-1$

Subtract $2y$ from both sides of the equation.

$-x=2y-1$

Multiply both sides by $-1$ .

$x=-2y+1=$

$x=color(red)(1-2y$

Substitute $color(red)(1-2y$ for $x$ in Equation 2 and solve for $y$ .

$3(color(red)(1-2y))-y=-4$

Expand.

$3-6y-y=-4$

Subtract $3$ from both sides.

$-6y-y=-4-3$

Simplify.

$-7y=-7$

Divide both sides by $-7$ .

$y=(color(red)cancel(color(black)(-7)))^1/(color(red)cancel(color(black)(-7)))^1$

$y=color(teal)1$

Substitute $color(teal)1$ for $y$ in Equation 1.

$-x-2(color(teal)(1))=-1$

Simplify.

$-x-2=-1$

Add $2$ to both sides.

$-x=-1+2$

Simplify.

$-x=1$

Multiply both sides by $-1$ .

$x=-1$

Point of intersection : $(-1,1)$

graph{(-2y-x+1)(-y+3x+4)=0 [-10, 10, -5, 5]}

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How do you solve the following system?: $-x -2y =-1, 3x -y = -4$

1 Answer

Explanation:

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Science

Math

Humanities

... and beyond

How do you solve the following system?: -x -2y =-1, 3x -y = -4-x -2y =-1, 3x -y = -4

1 Answer

Explanation:

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Impact of this question

How do you solve the following system?: $-x -2y =-1, 3x -y = -4$