Rick bought 3 shirts for $18 each, 2 pair of socks for $3.99 a pair, and a pair of slacks for $45.00. the sales tax rate is 8.5%. how much did he pay.

What number should be added to the expression x^2+3x+ in order to create a perfect square trinomial? 3/2 3 9/4 9

The anwser cause i do not understand just plez

If mary had 320 toy cars and she gave her friend 50 cars and then she gave her brother 72 more cars how much toy cars would mary have left ● explain with proper details