The answer is y = 2x + 0 or y = 2x.
The line passes through (0,0) and (1,2). The slope is
m = (2 − 0)/(1 − 0) = 2.
(You could also see this by drawing the two points and a slope triangle and use the rise/run idea of slope.)
In the slope-intercept form, y = mx + b, you now know that m = 2 and b = 0, so the answer is
y = 2x + 0 or y = 2x.
