Can anyone help me please

How do i put 3(x+7) in distributive property

The vertices of a triangle are a(7.5), b(4,2), and c19. 2). what is

Abicycle training wheel has a radius of 3 inches. the bicycle wheel has a radius of 10 inches.approximately how much smaller, in square inches and rounded to the nearest hundredth, is the area of the training wheel than the area of the regular wheel? *