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Recap: Around the Edge

Part of the Triangles section of Coddy's Geometry journey. Lesson 16 of 63.

Challenge

△DEF is isosceles and its perimeter is 43. Use the figure to write an equation, then solve it for x.

Then press Check.

Try it yourself

$Use the figure to find x$

Use the figure to find x

All lessons in Triangles

2The Triangle Inequality

Can Three Sticks Meet?Exactly Reaching The Range of the Third Side The Formula Recap: The Third Side

5The Pythagorean Theorem

Squares on the Sides Finding the Hypotenuse Pythagorean Triples When It Is Not Whole Recap: The Hypotenuse

8Special Right Triangles

The 45-45-90 Triangle Legs from the Hypotenuse The 30-60-90 Triangle All Three Sides Which Triangle Is It?Recap: Special Triangles

11Two Tools at Once

Height of an Isosceles Area from the Height The Equilateral Triangle Right Triangle Perimeter Recap: Two Tools

3Perimeter

Around the Edge A Missing Side Isosceles Perimeter Sides as ExpressionsRecap: Around the Edge

6Finding a Leg

Working Backwards The Ladder Which Side Is c?A Leg That Is Not Whole Recap: Finding a Leg

9Similar Triangles

Same Shape, Different Size The Scale Factor Finding a Side Matching the Corners Recap: Similar Triangles

12Final Challenges

Final: Three Sticks Final: The Fence Final: The Ladder Final: The Shadow Final: Master of Triangles