Question

If the slope of the line that passes through the points (a,0) and (1,2) is 1/2, what is the value of a?

Answer 1

draw a picture of a line through 1,2 with slope 1/2...

Answer 2

...

Answer 3

(y-2) = (1/2)*(x-1) also works

Answer 4

(let y = 0 and solve that equation for x)

Answer 5

Just use the formula to figure out slope: rise over run
It's change in y over change in x
\[(y2-y1)/(x2-x1)=(2-0)/(1-a)=2/(1-a)\]

Answer 6

\[2/(1-a)=1/2\]
\[1-a=1/4\]
\[-a=-3/4\]
a=3/4