Write the Equation

Part of the Angles section of Coddy's Geometry journey. Lesson 10 of 62.

In earlier lessons, the equation was supplied. Here, use the diagram to identify the angle relationship and write the equation yourself.

$Two angles on a straight line, 130 degrees and x plus 10 degrees$

The two adjacent angles form a straight angle. Their measures are (x + 10) degrees and 130°, so (x + 10) + 130 = 180. This task asks you to write the equation; you do not need to solve it.

Challenge

Easy

Two angles stand together on a straight line: (x + 25)° and 90°.

$Two angles on a straight line, x plus 25 degrees and 90 degrees$

Write the equation the figure states. Do not solve it.

Test yourself

This lesson includes a short quiz. Start the lesson to answer it and track your progress.

Test yourself

This lesson includes a short quiz. Start the lesson to answer it and track your progress.

All lessons in Angles

2Straight Lines and Supplements

Angles on a Line Supplementary Angles Three Angles on a LineWrite the EquationRecap: Along the Line

5Around a Point

Angles Around a Point The Missing Angle Equal Slices Four Angles, One Point Recap: The Full Turn

8Transversal Problems

Both Angles Labeled Verticals Meet Parallels From Figure to Equation Alternate with Algebra Recap: Through the Strip

11The Exterior Angle

The Exterior Angle Using the Shortcut Two Roads, One Answer Exterior in the Wild Recap: Outside View

3Right Angles and Complements

Complementary Angles Finding the Complement Perpendicular Lines Equal Parts of a Corner Recap: The Right Corner

6The Angle Bisector

The Angle Bisector Bisected Expressions Bisecting a Straight Angle Recap: Split in Half

9Triangle Angle Sum

The 180 Rule Finding the Third Angle Two Unknown Angles Right Triangles Recap: The Budget

12Final Challenges

Final: The Angle Chase Final: Triangle Meets Line Final: The Full Round Final: Isosceles Chase Final: Master of Angles