As we know the formula to calculate the line of equation is y - y1 = m (x - x1)
Where m is the slope. y1 is the first y co ordinate. x1 is the first x co ordinate.
Now we do know that the slope of parallel line is the same as the slope of the original line.
So parallel line slope is 3 so slope for our line is 3. Hence equation is y - 7 = 3 (x - 2) which becomes y = 3x + 1.