11.2E: Systems of Linear Equations with Three Variables (Exercises)
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For the following exercises, solve the system of three equations using substitution or addition.
11.
0.5 x-0.5 y=10
-0.2 y+0.2 x=4
0.1 x+0.1 z=2
12.
5 x+3 y-z=5
3 x-2 y+4 z=13
4 x+3 y+5 z=22
13.
x+y+z=1
2 x+2 y+2 z=1
3 x+3 y=2
14.
2 x-3 y+z=-1
x+y+z=-4
4 x+2 y-3 z=33
15.
3 x+2 y-z=-10
x-y+2 z=7
-x+3 y+z=-2
16.
3 x+4 z=-11
x-2 y=5
4 y-z=-10
17.
2 x-3 y+z=0
2 x+4 y-3 z=0
6 x-2 y-z=0
18.
6 x-4 y-2 z=2
3 x+2 y-5 z=4
6 y-7 z=5
For the following exercises, write a system of equations to solve each problem. Solve the system of equations.
19. Three odd numbers sum up to 61 . The smaller is one-third the larger and the middle number is 16 less than the larger. What are the three numbers?
20. A local theatre sells out for their show. They sell all 500 tickets for a total purse of \$ 8,070.00 . The tickets were priced at \$ 15 for students, \$ 12 for children, and \$ 18 for adults. If the band sold three times as many adult tickets as children's tickets, how many of each type was sold?