What is the equation of the line that passes through (0, 3) and (7, 0)?
a; y=3/7x-3
b: 3/7x+3
c: -3/7x+3
d: -3/7x-3

The answer should be (C):y=(-3/7)x+3 because:

 if you use the slope formula: (Y2-Y1)/(X2-X1) it would look like this:

(0-3)/(7-0) and the slope of the line would be -3/7

then using the slope you just found, plug it into the y=mx+b equation along with one set of coordinates to find b (the y-intercept):

y=mx+b
0=(-3/7)(7)+b
b=3

SO, overall if you put the slope (m) and the y-intercept (b) that you found together, you get the line formula of y=(-3/7)+3