If x + y = 3 and y/x =2, then y is equal to what?

Question

If x + y = 3 and y/x =2, then y is equal to what?

Answer 1

x + y = 3

 

y/x = 2, so y = 2x      [Just multiply both sides of the equation by x]

 

Since y=2x, substitute 2x for y:

 

x + y = 3

 

x + 2x = 3         [Replaced the y with 2x]

 

3x = 3

 

x = 1

 

So y = 2x = 2*1 = 2

 

Check:

x + y = 3

1 + 2 = 3

3 = 3

Check!