The equation of the line passing through (1,11) and (-4,5) can be expressed in the form x/a + y/b = 1. Find a.
+128475 x/a + y/b = 1 manipulate as follows
bx + ay = ab
ay = -bx + ab
y = (-b/a)x + b (1)
The slope of the given line = [ 5 -11] / [ -4 - 1] = [-6] / [-5] = 6/5
The equation of this line can be written as
y = (6/5) ( x - 1) + 11
y = (6/5)x - 6/5 + 11
y = (6/5)x -6/5 + 55/5
y = (6/5)x + 49/5 (2)
Comparing (1) and (2), b = 49/5
So
-b /a = 6/5
(-49/5) / a = 6/5
-49/a = 6
a = -49/6
