Holt Algebra 2. All rights reserved. Name. Date. Class. LESSON. 4-4. Practice B.
Determinants and Cramer's Rule. Find the determinant of each matrix. 1. 8. 2. 4.
Name LESSON
4-4
Date
Class
Practice B Determinants and Cramer’s Rule
Find the determinant of each matrix. 1.
8
2
6
2.
4 1
3
3.
9 5
16 1
0
1
2
6
8
3
7
3
0 1
4. 5 2
2
5.
0 4
5
2
4
3
1
1 1
36
10 4 6.
3
1
7 2
0
1 1
2
30
31
Use Cramer’s rule to solve each system of equations. 7.
{ 2x3x 3y2y 1 16
8.
{ 4x3x 3y2y 928
10, 7 10.
33 { 4y2y 5x 3x 11
9.
{ 8x3x 3y2y 2011 1, 4
6, 5 11.
{
27 4y 3x 1x 8 y __ 3
12.
{ 7165y2y4x5x0 0
3, 9
5, 2
2, 3
Solve. 13. On Monday, Marla babysat for 4 hours, did yard work for 2 hours, and earned a total of $41. On Friday, she babysat for 5 hours, did yard work for 3 hours, and earned a total of $55.
{
a. Write a system of equations. Let x Marla’s hourly rate for babysitting, and y her hourly rate for yard work.
4 5
b. Write the coefficient matrix. Evaluate its determinant.
d. What is Marla’s hourly rate for each activity?
a207c04-4_pr.indd 28
2 4 ; det 3 5
2 2 3
x 6.5; y 7.5
c. Use Cramer’s rule to find x and y.
Copyright © by Holt, Rinehart and Winston. All rights reserved.
4x 2y 41 5x 3y 55
28
Babysitting: $6.50, yard work: $7.50 Holt Algebra 2
12/26/05 6:27:12 AM Process Black
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Copyright © by Holt, Rinehart and Winston. All rights reserved.
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Holt Algebra 2
12/26/05 6:25:44 AM
