Download Math 120 Chapter 3 Review 1) Solve y = 4x + 4 2y + 10x = 26 2

Math 120 Chapter 3 Review
1) Solve
y = 4x + 4
2y + 10x = 26
2) Solve
8x - 9y = 2
-24x + 27y = -4
3) Solve
3x + 4y + z = 1
2x - 4y - z = -26
2x + y + 5z = -25
4) Write the augmented matrix , then row-reduce it to solve the system:
5) Evaluate the determinant:
-3 9
-8 8
6) Evaluate the determinant:
-5 5 3
-3 0 5
1 0 5
7) Solve the system by Cramer's Rule:
x - y + 5z = 3
4x +
z = 0
x + 4y + z = -12
-3x + 5y - z = 2
x - 5y - 5z = -46
-2x + y + z = 2
8) Graph the system of linear inequalities.
2x + 3y ≤ 6
4x + y ≤ 5
x≥0
y≥0
9) Katie Smith scored 40 points in a recent basketball game without making any 3-point shots. She scored 25
times, making several free throws worth 1 point each and several field goals worth two points each. How
many free throws did she make? How many 2-point field goals did she make?
10) Find an expression for the general solution to the system:
x - 7y - z = 9
3x - 21y - 3z = 27
-3x + 21y + 3z = -27
Answer Key
MATH 120 REVIEW CHAPTER 3
1) (1, 8)
2) ∅
3) (-5, 5, -4)
4)
1 -1 5
3
4 0 1
0 ; (0, -3, 0)
1 4 1 -12
5) 48
6) 100
7) (4, 4, 6)
8)
y
5
-5
5
-5
9) 10 free throws, 15 field goals
10) {(x, y, z) x - 7y - z = 9}
x