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Home > AC > Chapter 7 > Lesson 7.3.1 > Problem 7-87

7-87.

Solve the following systems of equations. Remember to check your solution in both equations to make sure it is the point of intersection.

  1. One way to solve this system of equations is by using the substitution method.

    . Substitute :

    Solve for .

    Distribute the left side.

    Combine like terms.

    Subtract on both sides.

    Use the solution you found for and substitute it into either original equation and solve for .

  1. One way to solve this system of equations is by using the elimination method.

    Multiply the top equation by .

    Add the two equations together by combining like terms.

    Solve for .

    When you find , you can now substitute the value into either original equation and solve for .

    Don't forget to check your solution!