Question

If x – y = 6 and x is twice the value of y, what is the value of x + y ?

Answer 1

x is twice the value of y can be written as:

x= 2y

then we replace x with 2y in the given equation

x - y = 6

2y - y = 6

y = 6

then to find x we replace y with 6 in either of the equations

x = 2y

x = 2(6) = 12

or

x - 6 = 6

x= 6 + 6 = 12

now find value if x + y

12 + 6 = 18

Answer 2

18

Explanation:

x - y = 6

Given: 2x - x = 6 since x is twice the value of y.

x = 6

2x = 6 · 2 = 12

12 + 6 = 18