250 likes | 565 Views
Bring vocabulary folder and note cards to class on Friday. 2-7-13 Equations to find missing angles EQ: How can you write and equation to find the measure of missing angles?. 1. 2. 3. 4. Check Homework. X = 30. X=50. x=-3. x+59+84+x+51=180 2x + 194 = 180. x= -7.
E N D
Bring vocabulary folder and note cards to class on Friday. 2-7-13 Equations to find missing angles EQ: How can you write and equation to find the measure of missing angles? 1. 2. 3. 4.
Check Homework X = 30 X=50 x=-3
x+59+84+x+51=180 2x + 194 = 180 x= -7
Writing Equations to Find Missing Angles Unit 7 Math 7
Objective-To find missing angles using rules of geometry. Supplementary Angles- Angles whose sum is 180 . a b
Find the value of x. x 30 x + 30 = 180 - 30 - 30 x = 150
Find the supplement of the given angle. 1) 40 140 5) 89 91 2) 18 162 6) 23 157 3) 153 27 7) 131 49 4) 65 115 8) 118 62
Write a variable equation and solve. Find an angle whose supplement is 30 less than twice the angle. x 2x - 30 x + (2x - 30) = 180 3x - 30 = 180 +30 +30 3x = 210 70 x = 70
- Angles whose sum is 90 . Complementary Angles b a x+ 40 = 90 - 40 -40 x 40 x = 50
Find the complement of... 1) 20 70 2) 47 43 No complement 3) 100
Write a variable equation and solve. Find an angle whose complement is 20 more than three times the angle. x + 3x + 20 = 90 x 4x + 20 = 90 3x + 20 - 20 -20 4x = 70 4 4 x = 17.5
- the sum of the interior angles of any triangle is always 180 . 180 Rule for Triangles b 80 x 40 a c 40 + 80 + x = 180 120 + x = 180 x = 60
Find each angle below. y + 14 = 63 2y - 10 2y - 10 = 88 y - 20 = 29 y+14 y - 20 180 (y + 14) + (2y - 10) + (y - 20) = 180 4y - 16 = 180 +16 +16 4y = 196 y = 49
Vertical Angles Theorem - the opposite angles of intersecting lines must be equal.
Vertical Angles Theorem - the opposite angles of intersecting lines must be equal. Find the missing angles a, b and c. What’s the relationship between angles a and b? 25 155 b c a 155 25
Find the missing angle. x 48 40 132
Summary: How can you write and equation to find the measure of missing angles? Homework: Vocabulary quiz on Friday; Handout; Test on Monday, 2-11-13 Bring vocabulary folder and extra cards on Friday.