Question

during a sale at the local department store, you buy three sweatshirts and two pairs of sweatpants for $85.50. later you return to the same store and buy three more sweatshirts and four more pairs of sweatpants for $123. what is the sale price of each sweatshirt and each pair of sweatpants?

Answer 1

3s + 2p = 85.50....multiply by -1
3s + 4p = 123
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-3s - 2p = -85.50 (result of multiplying by -1)
3s + 4p = 123
--------------------add
2p = 37.50
p = 37.50/2
p = 18.75 <=== cost of the pants

3s + 4p = 123
3s + 4(18.75) = 123
3s + 75 = 123
3s = 123 - 75
3s = 48
s = 48/3
s = 16 <=== cost of each shirt