Which expressions are equivalent to 4d + 6 + 2d?

Question

A. 2(3D+3)

B. 6(d+6)

C. (3D+3)+(3D+3)

Answer 1

4D + 6 + 2D = 6D + 6  = 2(3D + 3) <--- A is correct 

 

                    

 4D + 6 + 2D = 6D + 6 = 6(D +1) <--- B is NOT correct

 

4D + 6 + 2D = 6D + 6 = 3d + 3d + 3 + 3 = (3d + 3)+(3d +3) by associative and commutative properties

    so C is correct

 

A and C are both correct.