Skip to main content
Mathovia

Math Practice

Tangent Lines and Normal Lines Practice Problems

Find the point (a, f(a)), find the slope f′(a), then write the line. Type the right-hand side of y = ... for each line.

Written by
MPhil in Mathematics, Founder of Mathovia
Published

Mathematics verification: Mathematical formulas, calculations, worked examples and solutions are reviewed for accuracy before publication. How we check our work

Tangent Lines and Normal Lines Practice Problems

These problems follow the tangent lines and normal lines lesson. They start with tangent lines to polynomials and build up to normal lines, a given slope, a circle and a product.

The method

  1. The point: plug into the function to get .
  2. The slope: differentiate and plug in to get . For a normal line, use .
  3. The line: , then solve for .

Common mistakes to watch for

  • Leaving in the slope instead of plugging in .
  • Taking the y-coordinate from instead of from .
  • Using for the normal slope instead of the negative reciprocal .

Frequently Asked Questions

How should I type my answer?+

Type only the right-hand side of y = ..., in terms of x. For example, for y = 6x − 9 type 6x - 9. Fractions like x/4 + 1 and constants like e and pi are fine.

Do I have to write the line in slope-intercept form?+

No. Any equivalent expression is accepted, so 2 + (x - 4)/4 and x/4 + 1 are both marked correct.

More practice problems