What does a linear function look like

(if f(x)=4x^2 and g(x)=x+1, find (f o g)(x)

Which of the following statements is not true? a.parallel lines are lines in the same plane that never intersect. b.congruent figures have the same shape and same size angles and sides. c.similar figures must have the same shape and the same size. d.a rotation is when you turn a figure around a certain point.

Solve the given system of equations. 2y= -x+9 , 3x-6= -15