http://www.ck12.org Chapter 8. Systems and Matrices
Practice
Solve each system of equations using the elimination method.
1.x+y=−4;−x+ 2 y= 13
2.^32 x−^12 y=^12 ;− 4 x+ 2 y= 4
3. 6x+ 15 y=1; 2x−y= 19
4.x−^23 y=− 32 ; 5x− 2 y= 10
5.− 9 x− 24 y=−243;^12 x+y=^212
6. 5x+^283 y=^1763 ;y+x= 10
7. 2x− 3 y=50; 7x+ 8 y=− 10
8. 2x+ 3 y=1; 2y=− 3 x+ 14
9. 2x+^35 y=3;^32 x−y=− 5
10. 5x= 9 − 2 y; 3y= 2 x− 3
11. How do you know if a system of equations has no solution?
12. If a system of equations has no solution, what does this imply about the relationship of the curves on the graph?
13. Give an example of a system of two equations with two unknowns with an infinite number of solutions. Explain
how you know the system has an infinite number of solutions.
14. Solve:
12 ·^1 x− 18 ·^1 y= 4
8 ·^1 x+ 9 ·^1 y= 5- Solve:
14 ·^1 x− 5 ·^1 y=− 3
7 ·^1 x+ 2 ·^1 y= 3