Question

For the straight line defined by the points (2, 57) and (4, 91) , determine the slope and y-intercept. Do not round the answers.

Answer 1

The slope : 
m = (91 - 57 ) / ( 4 - 2 ) = 34 / 2 = 17
The line: y = m x + b
57 = 2 · 17 + b
57 = 34 + b
b = 57 - 34 = 23
Answer: the slope is 17 and y-intercept is 23.