Know how to make an equation of a line?

Question

There are three questions...

1. What is the equation of a line through points (5,-6) and (6,7)?

2. What is the equation of a line that passes through points (-3, -7) and (-4, 3)?

3. What is the equation of a line parrallel to this ^ one ( Question 2)that goes through (1,2)?


First correct answer gets the 10 points! :-)

Answer 1

first determine the slope

In question 1, the slope is (7+6)/(6-5) = 13.
The equation can be put into the format
y - y1 = m(x - x1)
y + 6 = 13(x - 5)

The second question is
y + 7 = -10(x + 3)

The third is
y - 2 = -10(x - 1)

Answer 2

1. The slope of this line is13/1 =13
Therefore, Y=13X+B ( now substitute) 7=13*6+B
B=-71
Therefore, Y=13X-71
2. The slope of this line is 10/-1 =-10
Y=-10*X+B (now substitute) 3=-10*-4+B B=-37
Y=-10X-37
3. Same slope=-10 (substitute) 2=-10*1+B B=12
Y=-10x+12