A line has a slope of 3/7 and its y-intercept is (0,18). What is its x-intercept?
Let two points on the line be (0, 18) and (x , 0)
We can solve this
[ 0 -18 ] / [ x - 0 ] = 3/7
-18 / x = 3/7
-18 (7/3) = x
(-18/3)(7) = x
-42 = x = the x intercept
