About Solving Systems by Elimination:

Another alternative to solve a linear system is known as the elimination method. When we use this method we place each equation in standard form. We then add the left sides together and the right sides together in such a way that a variable is eliminated. From this, we can obtain our solution.


Test Objectives
  • Demonstrate an understanding of a system of linear equations
  • Demonstrate the ability to solve a system of linear equations by elimination
  • Demonstrate the ability to check the solution for a system of linear equations
Solving Systems by Elimination Practice Test:

#1:

Instructions: Solve each linear system by elimination.

a) 7x + 10y = 4 : -2x - 5y = -14


#2:

Instructions: Solve each linear system by elimination.

a) 2x + 5y = 5 : -4x - 10y = -10


#3:

Instructions: Solve each linear system by elimination.

a) 8x - 32 = -8y :

-y - 5x = -32
 3  3

#4:

Instructions: Solve each linear system by elimination.

a) 7y + 34 = -12x : 20 + 8y = -9x


#5:

Instructions: Solve each linear system by elimination.

a) -30 + 6x = -14y :

y = -3x + 12
  7 7

Written Solutions:

#1:

Solutions:

a) (-8,6)


#2:

Solutions:

a) infinite number of solutions


#3:

Solutions:

a) (10,-6)


#4:

Solutions:

a) (-4,2)


#5:

Solutions:

a) no solution