Question

Please help asap!!!

Answer 1

The primary way in which a linear function stands out from other functions is that the independent variable, usually x, has the exponent 1:  x^1 or just x.

Thus, we must immediately elimiinate A and C.  

If you meant (1/3)x in B, then B is a linear function; if you meant 1 / (3x), then B is not a linear function.

Safest choice is D, supposing that by 2/3x=y-1 you actually meant

(2/3)x=y-1.  You could solve this for y:  y = (2/3)x + 1.

Answer 2

If x < 18 then you can subtract both sides by 18 and you would get x - 18 < 18 - 18 = 0

So that would be x - 18 < 0.

Hope this helps.