Which equations have equivalent expressions?

Check all that are true.

A. 2t + 3t = 6t

B. y + y + y = y(1 + 1 + 1)

C. 3(2 + x) = 6 + 3x

D. 2a + 2b = 4ab

E. x + 3 = 4x

Based on what i know about mean, this doesn't add up.

The function ƒ is defined by ƒ(x) = (x + 3)(x + 1). the graph of ƒ in the xy-plane is a parabola. which interval contains the x-coordinate of the vertex of the graph of ƒ?

Given: and prove: what is the missing reason in the proof? given transitive property alternate interior angles theorem converse alternate interior angles theorem