### Home > APCALC > Chapter 11 > Lesson 11.1.2 > Problem 11-26

11-26.

**Multiple Choice: **A

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Sketch the situation. Your sketch should have similar right triangles.

If the child's distance from the light is and their shadow length is

*, then:*

The equation can be rewritten as

Now differentiate.

Now use the information given in the problem to solve for .