Please help me I have been stuck

Tanya has $42 to spend at the dolphin island store. tshirts sell for $7 each and a pair of sunglases sells for $6.tanya buys 3 tshirts. how many pairs of sunglases can she buys with the amount of money she has left

Asquare and an equilateral triangle have the same perimeter. each side the triangle is 4 inches longer than each side of the square. what is the perimeter of the square

F(x)=5/6x+3 which of the following is true