Solving systems of equations by elimination

Solving systems of equations by elimination

The third method to find the solution of a system of equaitons

Multiple Choice

1. Which of following is a system of equation?

• 2x-4=6

• 2x>4-y and x=y+1

• x-y=2 and 2x+y=5

• 2x-3y=3

Multiple Choice

2. How many variables are there in the system 2x+y=2 and 2x-3y=7?

• 1

• 2

• 3

• 4

3 main steps to solve a system by elimination

• Find/create the same coefficient or opposite coefficient of a variable.

• Add/ subtract two equation to eliminate a variable.

• Solve for the value of each variable.

Multiple Choice

3. What should be the first step to solve the system of equations 2+5y=17 and 6x-5y=-9?

• Add teo equations to eliminate y.

• Subtract two equations to eliminate y.

• Add two equations to eliminate x

• Subtract two equations to eliminate x.

Multiple Choice

4. What is the solution of the system 5x-6y=-32 and 3x+6y=48?

• (7, 2)

• (-7,2)

• (2,7)

• (-2,7)

Multiple Choice

5. What is the solution of the system of equations -3x-3y=9 and 3x-4y=5?

• (2, 1)

• (-2, -1)

• (1,2)

• (-1,-2)

A system can has one solution, infinitely many solutions or no solution.

Multiple Choice

6. How many solutions does the system y=x+3 and y=x-1 have?

• No solution

• One solution

• Infinite many solutions

Multiple Choice

7. How many solutions does the system y-x=5 and 3y=3x+15?

• No solution

• One solution

• Infinite many solutions

Multiple Choice

8. How many solutions does the system 2x+4y=22 and 2x-2y=-8 have?

• one solution

• no solution

• infinitely many solutions

Multiple Choice

9. When solve a system of equations we got x=5 and y=2 then the solution of that system is.......

• (2, 5)

• (5, 2)

• (-2, 5)

• (-5, 2)

Multiple Choice

10. The theater club sells a total of 101 tickets to its first play. A student ticket costs $1. An adult ticket costs $2.50. The total ticket sales are $164. If let x be the number of adult tickets sold and y be the number of student tickets sold, which should be a system of equations represents this situation?

• x+y=164 and x+2.5y=101

• x+y=101 and 2.5x+y=164

• x+y=164 and 2.5x+y=101

• x+y=101 and x+2.5y=164

Multiple Choice

11. Washing 2 cars and 3 trucks takes 130 min. Washing 2 cars and 5 trucks takes 190 mins. How long does it take to wash each type of vehicle?

• 1 car takes 20 min and a truck takes 30 min.

• 1 car takes 20 min and a truck takes 20 min.

• 1 car takes 40 min and a truck takes 10 min.

• 1 car takes 10 min and a truck takes 40 min.