(a)

Observe the graph .

Slope of a tangent line with points and : .

Consider two points on the tangent line passing through the point .

The points on the tangent line are  and

Slope of the tangent line: .

The slope of the tangent line at is .

Consider two points on the tangent line passing through the point .

The points on the tangent line are and

Slope of the tangent line: .

The slope of the tangent line at is .

(b)

Observe the graph .

Slope of a tangent line with points and : .

Consider two points on the tangent line passing through the point .

The points on the tangent line are and .

Slope of the tangent line: 

The slope of the tangent line at is .

Consider two points on the tangent line passing through the point .

The points on the tangent line are  and .

Slope of the tangent line:

The slope of the tangent line at is .

(a)

The slope of the tangent line at is .

The slope of the tangent line at is .

(b)

The slope of the tangent line at is .

The slope of the tangent line at is .