What error did Sukant make? He did not add the values correctly. He did not find the correct absolute values. He should have used the y-coordinates. He should have subtracted the values.

Julie goes to the sports store and spends $40.50 before tax. she buys a pair of shorts for $21.75 and 3 pairs of socks that each cost the same amount. how much does each pair of socks cost? $$