Answer:
A,C,D,E
Step-by-step explanation:
The first one is true because in fact, supplementary angles' measures add up to 180°.
The second one is false because there are 5 types, not 3. These are the types:
acute angle-an angle between 0 and 90 degrees.
right angle-an 90 degree angle.
obtuse angle-an angle between 90 and 180 degrees.
straight angle-a 180 degree angle.
reflex angle- a angle between 180 and 360 degrees.
Third is true too because linear pair means two angles that form a straight line, or 180°.
Fourth is true because straight Angle theorem states that all the straight angles are 180 degrees. If the legs are pointing exactly in the opposite directions, then it forms a straight angle.
Last one is true because by definition complementary angles always form a right angle, which is 90°.
Hope it helps!
Answer:
The equation of the relation ⇒ 
y = 18
Step-by-step explanation:
∵ y ∝ x/z
∴ y = kx/z
∵ y = 18 , x = 15 and z = 5
∴ 18 = 15k/5 ⇒ 18 = 3k
∴ k = 18/3 = 6
∴ y = 6x/z
∵ x = 21 and z = 7
∴ y = (6 × 21)/7 = 18
