7.2 Law of Cosines Day 1 Thurs Feb 12 Do Now Find the area of the triangle ABC given A = 113deg, b = 18.2 cm, c = 23.7 cm.

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7.2 Law of Cosines Day 1 Thurs Feb 12 Do Now Find the area of the triangle ABC given A = 113deg, b = 18.2 cm, c = 23.7 cm

p.608 #17-31 odds

Law of Cosines In any triangle ABC, When the angle in between is a right angle, the law of cosines reduces to the Pythagorean Theorem

Ex1 Solve triangle ABC if a = 32, c = 48, B = degrees

Ex2 P.614 ex2

Ex3 Solve triangle RST if r = 3.5, s = 4.7, t = 2.8

Ex4 P.616 ex4

Closure When would we choose the law of sines or law of cosines when solving a triangle? HW: p.618 #1-15 odds

7.2 Law of Cosines Day 2 Tues Feb 17 Do Now Solve the triangle ABC, if possible B = 133 degrees, a = 12, c = 15

HW Review: p.618 #

When to use Law of Sines/Cosines Given the following sides/angles, SituationLaw to Use SSSLaw of Cosines ASALaw of Sines AASLaw of Sines SASLaw of Cosines SSALaw of Sines AAAneither

Closure Determine which law applies, then solve the triangle ABC given a = 15, c = 7, B = 62 degrees HW: p.619 #17-23 odds, odds