[SOLVED] Could someone tell me if my answers are correct please?

Thanks in advance for your help!

Find the slope and y-intercept of the following.

y=3x-5

My answer:

slope=3, y-intercept=-5

----------

Write an equation for the line with slope 1/3 and y-intercept 4.

My answer:

y=1/3x+4

Write an equation for the line with slope 3 going through point (1,-2).

My answer:

y=3x+(-2)

I also need help getting the formula to solve a question:

(I have already arrived at an answer, but I used logic and not a formula to get to it)

One eighth of the square root of 7 less than a number is 2 what is the number?

my answer:

263

I got to that answer by saying that if 2 was one eighth the square root of the number, minus seven, then 16=the square root and since 16^2=256 then the number must be 256+7=263

Thank you again for your help!

Drakmord