I need help asap.

I have been asked two questions i need advice on.

Both questions refer to the quadratic function y=-0.7x^{2}+3x+0.2+1.78

I have also attached the graph of this function, using DESMOS, it is attached as an .HTML file.

(BTW The equation refers to 'the perfect shot equation'. In basketball the perfect shot equation follows a quadratic function, wherein the ball thrown goes in every time. The data on the graph is in meters where the y-axis represents height and x-axis distance.

THE QUESTIONS I CANT FIGURE OUT:

"a) If the height of the basketball ring is 3m, show how you can use your equation to determine how far in from the baseline it is?"

!?!?

"b) Now you know the quadratic equation to shoot the perfect shot, but where do you need to stand? Investigate where your 'sweet spot' (the spot where your shot will follow the equation and go in every time) on the court is. Explain how you derived your answer. (Hint: use your graph to determine the distance from the basketball ring you need to be and check it using your equation)"

!?!?

Please help asap this bloody thing is due tomorrow.

Thanks in advance to any and everybody!