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Solve each system of equations algebraically. Verify the solution using the graph of the system.

Solve each system of equations algebraically. Verify the solution using the graph-example-1
User Rifthy
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1 Answer

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x = -2, y = -2/7

Step-by-step explanation:

6x - 7y = -10 ...equation 1

3x + 7y = -8 ...equation 2

Using elimination method to solve the equations:

To eliminate, we need to ensure the variable we want to eliminate has the same coefficient in both equations.

To eliminate y, this is because the coeffient are the same except for the sign in front of them.

We add both equations to eliminate y:

6x + 3x - 7y + (+7y) = -10 + (-8)

Multiplication of same sign gives positive number. Multiplication of opposite signs give negative number.

6x + 3x - 7y + 7y = -10 - 8

9x + 0 = -18

9x = -18

divide both sides by 9:

9x/9 = -18/9

x = -2

To get y, we insert the value of x in any of the equation

Using equation 1:

6(-2) - 7y = -10

-12 - 7y = -10

-7y = -10 + 12

-7y = 2

divide both sides by -7:

-7y/-7 = 2/-7

y = -2/7 = -0.286

The solution of the equations: x = -2, y = -2/7

Plotting the graph:

The point of intersection of both equation lines is the solution of the system. The point (x, y) is at (-2, -0.286)

Solve each system of equations algebraically. Verify the solution using the graph-example-1
User Adam Preble
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3.3k points