If your "base" function is y = x2
, then your new function is y = (3(x + 7/3))2
. Using the exact
values (almost uniformly the safer choice), the vertex has been shifted 7/3 to the left, and the parabola is only 1/3 as wide (or, to look at it another way, it is growing three times as fast).
So my only suggestion would be to edit your solution to use the exact value. Good job!