Explanation:
5.
y = 3
yes, that's it for this here too.
it means that any value for x is valid, and all have the assigned y value 3.
6.
remember, the usual equation for a line is
y = ax + b
"a" being the slope, "b" the y-intercept (the y-value when x = 0).
we see the y-value for x = 0 is 3. that is "b".
for the slope we need 2 points and calculate the x- and y- coordinate differences.
always look for points with integer coordinates.
I see e.g. (0, 3) and (3, 2).
x changes by +3 (from 0 to 3).
y charges by -1 (from 3 to 2).
the slope "a" = -1/+3 = -1/3
the equation is then
y = (-1/3)x + 3
7.
we do exactly the same things.
we see the y-value for x = 0 is +1. that is "b".
I see e.g. these points : (0, 1) and (3, 2).
x changes by +3 (from 0 to 3).
y changes by +1 (from 1 to 2).
the slope "a" is +1/+3 = 1/3.
the equation is
y = (1/3)x + 1
8.
and again the same things.
we see the y-value for x = 0 is +3. that is "b".
I see e.g. these points : (0, 3) and (-3, 0).
x changes by -3 (from 0 to -3).
y changes by -3 (from 3 to 0).
the slope "a" is -3/-3 = 3/3 = 1.
the equation is
y = x + 3