Answer:

Step-by-step explanation:
General equation of a parabola that opens up is
, a>0
So equation becomes
which implies option A and option B can never be true for this parabola.
Also this parabola's vertex lies in 3rd quadrant where coordinates of both x and y will be negative.
So, the equation of parabola will be of the form 
Hence, option 4 that is
is correct.
Look at my picture for the work
Answer: a=8 and b=2
Please let me know if this helped!!
145600.. . .. ...........
Suppose the sides of the big triangle are called m, x and 12+4=16. We have that the big triangle and the small triangle to the right of the shape (sides x,y,12) are similar. We can take then the ratios of correponding sides and know that they will be equal. Thus, we have that 4/y=y/12. Hence, y*y=48. Thus y=

.