Question

If y = 4x, x = 2z, and z = 3a, what is the value of y - x in terms of a?

A) -20a
B) -18a
C) 6a
D) 18a
E) 20a
With steps please

Answer 1

D) 18a

Explanation:

y - x

= 4x - x (plug y = 4x)

= 3x

= 3(2z) (plug x = 2z)

= 6z

= 6(3a) (plug z = 3a)

= 18a