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Week 3. Warm Up. 08.29.11. 1) What is a counter example for:. The sum of two numbers is always greater than the larger number.”. 2) Draw two straight lines that cross each other. Measure each angle. Describe the angles. Did you make any vertical angles? Did you make any linear pairs?.
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Week 3 Warm Up 08.29.11 1) What is a counter example for: The sum of two numbers is always greater than the larger number.” 2) Draw two straight lines that cross each other. Measure each angle. Describe the angles. Did you make any vertical angles? Did you make any linear pairs?
Rewind 1 30º 1 2 ∠1 and ∠2 are linear pairs m∠1 + m∠2 = 180º m∠1 + 30º = 180º m∠1 = 180º - 30º m∠1 = 150º
The measure of two angles when their sum is 90 º Complimentary Angles Ex 1 1 2 3 4 ∠1 and ∠2 are complimentary adjacent angles ∠3 and ∠4 are complimentary nonadjacent angles m∠1 + m∠2 = 90 º m∠3 + m∠4 = 90º
m∠A and m∠B are complementary Ex 2 Find both angles m∠A = 5x + 12 m∠B = 2x - 6 5x + 12 + 2x – 6 = 90º 7x + 6 = 90 7x = 90 - 6 7x = 84 x = 12
x = 12 m∠B = 2x - 6 m∠A = 5x + 12 = 5( 12 ) + 12 = 2( 12 ) – 6 = 60 + 12 = 24 – 6 m∠A = 72º m∠B = 18º
m∠ A and m∠ B are Complementary Ex 3 m∠B = ? m∠A = 48º m∠A + m∠B = 90º 48 + m∠B = 90 m∠B = 90 - 48 m∠B = 42º
Supplementary Angles The measure of two angles when their sum is 180º 1 Ex 4 2 ∠1 and ∠2 are supplementary adjacent m∠1 + m∠2 = 180º 3 4 ∠3 and ∠4 are supplementary nonadjacent m∠3 + m∠4 = 180º
m∠A and m∠B are Supplementary Ex 5 Find both angles m∠A = 7x - 248 m∠B = x + 44 7x - 248 + x + 44 = 180º 8x - 204 = 180 8x = 180 + 204 8x = 384 x = 48
x = 48 m∠B = x + 44 m∠A = 7x - 248 = 7( 48 ) - 248 = ( 48 ) + 44 = 336 - 248 m∠B = 92º m∠A = 88º
m∠ A and m∠ B are Supplementary Ex 6 m∠B = 121º m∠A = ? m∠A + m∠B = 180º m∠A + 121 = 180 m∠A = 180 - 121 m∠A = 59º
Review Complementary angles add up to ____º. Do 1: m∠ A and m∠ B are Supplementary m∠A = ? m∠B = 47º Textbook page 48, 37 – 53 all Assignment: