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Get a calculator, have warm up paper on your desk . Today’s class will have a lot of notes, be prepared. 1) – 23 – 65 – 45 – 89 + 37 + 51 + 124 2) Solve and graph the inequality: 7 > y/-14 3) What is the square root of 289?
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Get a calculator, have warm up paper on your desk. Today’s class will have a lot of notes, be prepared.
1) – 23 – 65 – 45 – 89 + 37 + 51 + 124 2) Solve and graph the inequality: 7 > y/-14 3) What is the square root of 289? 4) If angle A and angle B are supplementary angles and angle B is 42o what is angle A?
Line and Angle Relationships Lines that intersect to form a right angle are called perpendicular lines
Line segments that have the same length, or angles that have the same measure, or figures that have the same size and shape are called congruent. The symbol for is congruent tois
When two lines intersect, they form two pairs of opposite angles called vertical angles 2 3 1 4 Angles 1 & 3 have the same measure, and angles 2 & 4 have the same measure.
When two angles have the same vertex, share a common side, and do not overlap, they are adjacent angles. m ABC = m angle 1 + m angle 2 D C 2 A 1 B
Complementary Angles are adjacent angles that add up to 90o. Angle 1 + angle 2 = 90o 1 2 Supplementary Angles are adjacent angles that add up to 180o. Angle 1 + angle 2 = 180o 1 2
Parallel Lines – two lines in a plane that never intersect. a b a || b
When parallel lines are intersected with another line, this line is called a transversal. Eight angles are formed transversal 2 1 4 3 6 5 8 7
Alternate interior angles are on opposite sides of the transversal and inside the parallel lines; these angles are congruent to each other. 4 3 6 5
Alternate exterior angles are on opposite sides of the transversal and outside the parallel lines; these angles are congruent to each other. 2 1 8 7
Corresponding angles are in the same position on the parallel lines in relation to the transversal; these angles are also congruent to each other. 2 1 4 3 6 5 8 7
Okay, so if we know angle 2, what other angles do we know? How can I find out what angle 8 is? 2 1 4 3 6 5 8 7
Angles ABC and FGH are complementary. If m ∠ ABC = x + 8 and m ∠ FGH = x – 10, find the measure of each angle. Step one – Find the measure of x m ∠ ABC+ m ∠ FGH = 90o (x + 8) + (x – 10) = 90o 2x – 2 = 90o 2x = 92 x = 46o
Step 2 – Replace x with 46 to find the measure of each angle. M ∠ ABC = x + 8 = 46 + 8 or 54 M ∠ FGH = x - 10 = 46 - 10 or 36 We can then check our answer by adding 36 to 54 which should, and does equal 90.
Classwork – complete the classwork on my moodle page titled line and angle relationships classwork. Homework will be on Moodle titled: Homework Line and Angle relationships