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| Linear Pairs of Angles |
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| EEVblog:
So 8yo Sagan get these questions in his extension math class. And I'm like :-// |
| StillTrying:
B2 is 180/2 +/- 24/2 = 90 +/- 12 = 102 and 78 The second B2 is the same working 90 +/- 21 The images are tooo big. |
| Brumby:
"Linear pairs" ? ? ? When I was in school they were called supplementary angles. The English used to describe the actual question in B(1) on sheet 2 isn't all that clear to me. Seeing the answer makes it obvious, but the phrase used isn't how I would expect such an idea to be presented. Maybe I just need to spend some time in class and get used to the "new speak". I am a little surprised at these questions thrown at an 8 y.o. as a couple of them lean into algebraic processes. |
| bsudbrink:
Here's what I see: To solve Sheet 2, B2, it is clearest to use simultaneous equations: a+b=180 given by "In a linear pair of angles" a+24=b given by"one angle measures 24 more than the other" a+a+24=180 substitute a+24 for b 2a=156 subtract 24 from both sides and combine a a=78 divide both sides by 2 b=102 subtract 78 from 180 To solve Sheet 1, B2, same method as Sheet 2, B2: a+b=180 given by "a linear pair of angles" a-b=42 given by "the difference" ... "is 42" a=b+42 add b to both sides b+42+b=180 substitute b+42 for a 2b=138 subtract 42 from both sides and combine b b=69 divide both sides by 2 a=111 subtract 69 from 180 I assume the red mark on Sheet 1, B3 indicates that the instructor thinks there is an error... It looks correct to me. Maybe the instructor is being a stickler about the order??? |
| mrflibble:
For a short & clear definition, see http://www.mathwords.com/l/linear_pair_of_angles.htm For the longer version, see: https://en.wikipedia.org/wiki/Angle#Combining_angle_pairs Two angles that sum to a straight angle (1/2 turn, 180°, or π radians) are called supplementary angles. If the two supplementary angles are adjacent (i.e. have a common vertex and share just one side), their non-shared sides form a straight line. Such angles are called a linear pair of angles. |
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