7. Systems of Equations & Matrices

In Exercises 5–18, solve each system by the substitution method.5x + 2y = 0x - 3y = 0

In Exercises 5–18, solve each system by the substitution method.2x + 5y = - 43x - y = 11

Solve each system by substitution. See Example 1.7x - y = -10 3y - x = 10

In Exercises 5–18, solve each system by the substitution method.2x - 3y = 8 - 2x3x + 4y = x + 3y + 14

Solve each system by substitution. See Example 1.-2x = 6y + 18 -29 = 5y - 3x

Solve each problem using a system of equations. A company sells recordable CDs for $0.80 each and play-only CDs for $0.60 each. The company receives $76.00 for an order of 100 CDs. However, the customer neglected to specify how many of each type to send. Determine the number of each type of CD that should be sent.

In Exercises 5–18, solve each system by the substitution method.y = (1/3)x + 2/3y = (5/7)x - 2

Solve each system by substitution. See Example 1.3y = 5x + 6 x + y = 2

Solve each system by elimination. In systems with fractions, first clear denominators. See Example 2.4x + y = -23x - 2y = -17

In Exercises 19–30, solve each system by the addition method.x + y = 1x - y = 3

In Exercises 19–30, solve each system by the addition method.2x + 3y = 62x - 3y = 6

In Exercises 19–30, solve each system by the addition method.x + 2y = 2- 4x + 3y = 25

Solve each system by elimination. In systems with fractions, first clear denominators. See Example 2.5x + 7y = 6 10x - 3y = 46

In Exercises 19–30, solve each system by the addition method.4x + 3y = 152x - 5y = 1

Solve each system by elimination. In systems with fractions, first clear denominators. See Example 2.6x + 7y + 2 = 07x - 6y - 26 = 0