i need help @!!!!?

Question

it says write an equation for the line through each pair of points.how do u do this i dont get it .???
.(1,2),(3,4)

Answer 1

first you find the slope.
Y2 - Y1 divided by X2 - X1
so... 4-2 / 3-1 this equals 2/2 which equals 1
so your slope is 1

next use one of the equations to find your y-intercept
the first one (1,2)

y=mx + b is going to be your line equation
so
2=1(1)+b
2=1+b
subtract one from the other side, so you subtract it from the other
1=b

your line equation is
y=1x + 1 is your answer

Answer 2

See if this place helps ya.
http://www.algebrahelp.com/