# How do you find the slope of a line perpendicular to a tangent line?

## How do you find the slope of a line perpendicular to a tangent line?

Each normal line in the figure is perpendicular to the tangent line drawn at the point where the normal meets the curve. So the slope of each normal line is the opposite reciprocal of the slope of the corresponding tangent — which, of course, is given by the derivative.

What is the formula for slope of a tangent line?

Finding the Equation of a Tangent Line. Figure out the slope of the tangent line. This is m=f′(a)=limx→af(x)−f(a)x−a=limh→0f(a+h)−f(a)h.

### What is the perpendicular tangent theorem?

According to the Perpendicular Tangent Theorem, tangent lines are always perpendicular to a circle’s radius at the point of intersection. In other words, m is perpendicular to OP and n is perpendicular to OQ. In order for m and n to be parallel (never intersect), this means ∠POQ has to be 180°.

How do you find the slope of two parallel lines?

When given two points, (x 1, y 1) and (x 2, y 2), on a line, we can calculate the slope of the line using the formula (y 2 – y 1) / (x 2 – x 1). Because parallel lines run in the same direction, they have the same slope.

#### How do you know if a slope is perpendicular?

Explanation: If the slopes of two lines can be calculated, an easy way to determine whether they are perpendicular is to multiply their slopes. If the product of the slopes is , then the lines are perpendicular.

What is perpendicular in tangent?

The normal line is defined as the line that is perpendicular to the tangent line at the point of tangency. Because the slopes of perpendicular lines (neither of which is vertical) are negative reciprocals of one another, the slope of the normal line to the graph of f(x) is −1/ f′(x).

## How do I find the slope of the line?

Using two of the points on the line, you can find the slope of the line by finding the rise and the run. The vertical change between two points is called the rise, and the horizontal change is called the run. The slope equals the rise divided by the run: Slope =riserun Slope = rise run .

Is the derivative the slope of the tangent line?

The derivative of a function gives us the slope of the line tangent to the function at any point on the graph. This can be used to find the equation of that tangent line.