Drill 4: Solutions to equations
Determine whether the indicated number is a solution of the equation
1. 3x  9  15; x  2
2.  3 y  7  5; x  4
3. 5 x  8  27; x  7
Solve using the addition principle
4. x 17  4
5. y  13  4
6. m 14  3
Solve using the multiplication principle
7. 7 x  21
8.
2
x  14
5
9.  13 y  169
Solve
10. 12x 14  70
11.  8 y  5  45
12. 2x  8x  120
13.  4 y  13  13
14.  4 y  13  13
15. 5x  8x  117
16. 5x  8x  117
17. 3a  8  4a  6
18. Phil’s batting average is 0.300. This is about
4
as much as Joe’s average. What is
5
Joe’s average?
19. One phone company charges 65% of its normal long-distance rate after 5p.m. A dayrate long-distance call from San Francisco to Chicago costs 20 cents per minute. How
much is an 11-minute call between these two cities after 5 p.m.?