Question

Find an equation of the line containing the given pair of points (3,4) and (9,9)

Answer 1

y = 5x/6 + 3/2

Explanation:

First, find the slope (m):

m=(y2-y1)/(x2-x1)

m=(9-4)/(9-3)

m=5/6

y=mx+b ==> slope-intercept form equation

y = 5x/6 + b==> substitute the value of the slope for m

9 = 5(9)/6 + b ==> substitute a point (x, y) or (9, 9) into the equation

9 = 45/6 + b ==> simplify

(9 = 45/6 + b)*6 ==> multiply the equation by 6 to remove denominators

54 = 45 + 6b ==> simplify

54 - 45 = 45 - 45 + 6b ==> solve for b

9 = 6b

9/6 = 6b/6

b = 3/2

y = 5x/6 + 3/2 ==> plug in b for the slop-intercept equation