7.1 (Day 2) Coterminal Angles

Angles in Standard Position

I( +, + )

0

Vertex at originInitial side along pos x-axis

II( – , + )

III( – , – )

IV( + , – )

90

180

270

x

y

(0, 0)

60

150

Coterminal Angles

When placed in standard position, terminal sides coincide

n is any integer + n∙360

60

420

Ex 1) Find 2 (+) and 2 (–) angles that are coterminal to 37

39737 + 1∙360 =

75737 + 2∙360 =

–323

37 + (–1)∙360 = –

68337 + (–2)∙360

=

Triangles

180Sum of 3 ’s in = Oblique :

Isosceles : has 2 equal sides (& 2 = ’s)

If 2 ’s of one = 2 ’s of other → corresp. sides are proportional

Similar ’s:

Equilateral : all 3 sides are = (& 3 = ’s)

that is not a right

Ex 2) If a 6-foot man casts a 2-foot shadow & a building casts a 12-foot shadow,

how tall is the building?

2 12

x6

height

shadow

6

2 12

x 2 72x

36 feetx

Ex 3) Pg. 384 Example 5

6

20

52

x

height

hypotenuse

2 2

5 20 5

x

5( 2) 2(25)x 5 10 50x

5 40x 8 feetx

31 – 5 – 6 = 20

Small Large

Homework

#702 Pg. 385 41 – 48 all, 49 – 67 odd