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

An advertising firm has an old computer that can prepare a whole mailing in 6 hours. with the of newer model the job is complete in 2 hours. how long would it take the newer model to do the job alone?

What are the relative frequencies to the nearest hundredth of the columns of the two-way table? a b group 1 102 34 group 2 18 14

Agroup of students want to create a garden. they do not know the exact measurements but they propose using a variable to represent the length and width of the garden. the length of the garden is 10 feet longer than double the width. use a single variable to write algebraic expressions for both the length and width of the garden. write an algebraic expression for the area of the garden. use mathematical terms to describe this expression.