Help Me! Easy math homework help needed please! Find the value of x. Please do all 3!

The angle of a triangle are given as 6x,(x-3), and (3x+7). find x then find the measures of the angles

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

Ellie spent $88.79 at the computer stote. she had $44.50 left to buy a cool hat. how much money did she originally have? write and solve an equation to answer the question.