1. Lesson 1-0
Algebra Review

2. Language of Math
Language of Math is EQUATIONS! All work should be done with equations All calculations should have equations 3x + 20 – 4x – 10 is an expression; not an equation!

3. Rules of Equality
Add the same value to both sides of the equation Subtract the same value to both sides of the equation Multiply both sides of the equation by the same value Divide both sides of the equation by the same value

4. Typical Geometry Problems
Solve for x in the following: 6x – 12 = 4x + 18 (6x – 12) + (4x + 22) = 180 5x + (2x – 10) + (3x + 30) + 2x + (4x + 40) = 540

5. Problem 1 Solve for x in the following: 6x – 12 = 4x + 18 + 12 = + 12
+ 12 =
6x = 4x + 30
- 4x = - 4x
2x = 30
x = 15

6. Problem 2 Solve for x in the following: (6x – 12) + (4x + 22) = 180

7. Problem 3
Solve for x in the following: 5x + (2x – 10) + (3x + 30) + 2x + (4x + 40) = 540
16x = 540
16x = 480
x = 30

8. Common Mistakes
Add or subtracting the same value to both sides of a plus or minus; instead of both sides of the equation! Combining constants and coefficients of variables Adding instead of multiplying Subtracting instead of dividing

9. Check your Answer!
Homer Simpson test: Does the answer make any sense? Common warning signs: Never have a negative measure for angles or distance Almost never will x = negative number in Geometry (except on graphing problems)

10. Magic Geometry Numbers
90 – complementary (seen in right triangles!) 180 – supplementary (also seen in all triangles) 360 – once around a circle in angles or arcs

11. Round Two
Solve for x in the following: 8x – 12 = 4x + 28 (6x – 12) + (9x + 27) = 180 x + (2x + 20) + (4x – 10) + 2x + (4x – 40) + 2x = 720

12. Round Two – Problem 1 Solve for x in the following: 8x – 12 = 4x + 28
+ 12 =
8x = 4x + 40
- 4x = - 4x
4x = 40
x = 10

13. Round Two – Problem 2
Solve for x in the following: (6x – 12) + (9x + 27) = 180
15x = 180
15x = 165
x = 11

14. Round Two – Problem 3
Solve for x in the following: x + (2x + 20) + (4x – 10) + 2x + (4x – 40) + 2x = 720
15x – 30 = 720
15x = 750
x = 50