Slope, also known as "angular coefficient", indicates the degree of inclination of a straight line relative to the horizontal axis. The tangent of the angle between a straight line and the positive semi-axis of the horizontal axis of a plane rectangular coordinate system is the slope of the straight line relative to the coordinate system. If the straight line is perpendicular to the x-axis, the tangent of the right angle is infinite, so the straight line has no slope. When the slope of the straight line L exists, for the linear function y=kx+b, (slope-intercept form) k is the slope of the graph of the function.

When the slope of the line L exists, the slope-intercept form is y=kx+b. When k=0, y=b

When the slope of the straight line L exists, the point slope formula y2-y1=k(X2-X1)

When the line L has non-zero intercepts on the two coordinate axes, the intercept formula is X/a+y/b=1

For any point on any function, its slope is equal to the angle between its tangent and the positive direction of the x-axis, that is, tanα

Slope calculation: ax+by+c=0, k=-a/b.

Straight line slope formula: k=(y2-y1)/(x2-x1)

The product of the slopes of two perpendicular lines is -1: k1*k2=-1.