I had this big assignment to do, and I did most of the questions except for these few (or I did them and I'm not sure if that's how I go about working them out)

1. State the y_intercept of the line: 3x+4y = -3 with equations.

I did: 4y = 3x+8 / y_int = -8?

2. Show that (2, 1) lies on the same line with the equation y=2x+3

I started with: 2 x 2 + -3x1 = -3

3. Parallel to 3x-4y=2 passing through (1, 2)

I did: 3x-4y =3 x 1 - 4 x 1

=3x-4y=-1

4. Perpendicular to 3x-4y = 2 passing through (1, 2)

Absolutely no idea how to do this.

5. Two lines have slopes k+2=-1. Find k given that:

a. The lines are parallel

b. The lines are perpendicular

I got:

a. k+2 = -1

b. -1/2k

Can anyone please help me out with these?