I'll help with the first. So we have the equations:

(I)..

(II)..

To find the point of intersection with algebra, we just solve the system for x and y.

So let's substitute the value of y in (I) into (II):

Expand :..

Simplify:..

Factor:..

Now substitute our value of x into (I):

For the x value of 4:..

So we have the point:..

For the x value of -3, substituting it into (I), we get -4.

So we also have the other point

The graph agrees with my answer: