Question

Use the slope formula to determine the slope of a line that passes through the points (4, 9) and (-8, -6).

Answer 1

y = mx + c

gradient = -6-9/-8-4
= -15/-12
= 1.2

when x = 4 and y = 9,
9 = 1.2(4) + c
c = 9 - 4.8
= 4.2

The slope of the line is y = 1.2x + 4.2 .