NAME
DATE
3-7
PERIOD
Practice
Solving Systems of Equations Using Cramer’s Rule
Evaluate each determinant.
1.
⎪12 76⎥
2.
⎪93 26⎥ 0
3.
⎪-24 -51⎥
4.
-3
⎪-142 -2
⎥ 34
5.
⎪-124 -34⎥ -20
6.
-5
⎪25 -11
⎥
7.
⎪33.75 -45⎥ 30
8.
-1
⎪23 -9.5
⎥ -16
9.
⎪0.5
0.4
-5
-18
3
-0.7
0.13
-0.3
⎥
Evaluate each determinant using expansion by diagonals.
-2 3 1
10. 0 4 -3
2 5 -1
⎪
⎥
0 -4 0
13. 2 -1 1
3 -2 5
⎪
⎥
-48
2 -4 1
11. 3 0 9 45
-1 5 7
2 1 1
12. 1 -1 -2 7
1 1 -1
2 7 -6
14. 8 4 0 -72
1 -1 3
-12 0 3
15.
7 5 -1
4 2 -6
⎪
⎪
28
⎥
⎪
⎥
⎪
⎥
⎥
318
16. 4x - 2y = -6
3x + y = 18
17. 5x + 4y = 10
(3, 9)
19. 6x + 6y = 9
4x - 4y = -42
-3x - 2y = -8
18. -2x - 3y = -14
(6, -5)
5y = 54 + 3x
y
2
4
y
x
− - − = -6
4
6
x
+−=2
21. −
20. 5x - 6 = 3y
(-−92 , 6)
(1, 4)
4x - y = 0
(12, 18)
(-8, 24)
25. GEOMETRY Find the area of a triangle whose vertices have coordinates (3, 5), (6, -5),
and (-4, 10). 27.5 units2
26. LAND MANAGEMENT A fish and wildlife management organization uses a GIS
(geographic information system) to store and analyze data for the parcels of land it
manages. All of the parcels are mapped on a grid in which 1 unit represents 1 acre. If
the coordinates of the corners of a parcel are (-8, 10), (6, 17), and (2, -4), how many
acres is the parcel? 133 acres
Chapter 3
46
Glencoe Algebra 2
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
Use Cramer’s Rule to solve each system of equation.