BackSolve 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 + 2/3 y = (5/7)x - 2
Solve each system by substitution.
3y = 5x + 6
x + y = 2
Solve each system by elimination. In systems with fractions, first clear denominators.
4x + y = -23
x - 2y = -17
In Exercises 19–30, solve each system by the addition method. x + y = 1 x - y = 3
In Exercises 19–30, solve each system by the addition method. 2x + 3y = 6 2x - 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.
5x + 7y = 6
10x - 3y = 46
In Exercises 19–30, solve each system by the addition method. 4x + 3y = 15 2x - 5y = 1
Solve each system by elimination. In systems with fractions, first clear denominators.
6x + 7y + 2 = 0
7x - 6y - 26 = 0
In Exercises 19–30, solve each system by the addition method. 3x - 4y = 11 2x + 3y = - 4
Solve each system by elimination. In systems with fractions, first clear denominators.
x/2+ y/3 = 4
3x/2+3y/2 = 15
Solve each system by elimination. In systems with fractions, first clear denominators.
(2x-1)/3 + (y+2)/4 = 4
(x+3)/2 - (x-y)/2 = 3
In Exercises 19–30, solve each system by the addition method. 3x = 4y + 1 3y = 1 - 4x
In Exercises 31–42, solve by the method of your choice. Identify systems with no solution and systems with infinitely many solutions, using set notation to express their solution sets. x = 9-2y x + 2y = 13