Slope is given by the equation ymxb but you mistakenly identified b in this equation as the slope. Slope m change in y change in x y y 1 x x 1. When you work out the frictional forces you need to take this fact into account.
Text Slope dfrac goldD text Change in y greenD text Change in x dfrac goldD y_2 - y_1 greenD x_2 - x_1 Slope Change in xChange in y.
The slope of a line defines the steepness of the line and whether the line rises or falls. Instead the correct answer will be the constant m. Substitute the slope for m in the slope intercept form of the equation. When you work out the frictional forces you need to take this fact into account.