One song download costs $2 and one movie download costs $11.
Step-by-step explanation:
Let,
Price of one song download = x
Price of one movie download = y
According to given statement;
8x+9y=115 Eqn 1
15x+9y=129 Eqn 2
Subtracting Eqn 1 from Eqn 2

Dividing both sides by 7

Putting x=2 in Eqn 1

Dividing both sides by 9

One song download costs $2 and one movie download costs $11.
Keywords: linear equation, elimination method
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