For number 15 and 16, you just have to find the absolute difference between the two points along the calibration of the protractor.
15. ∠BXC = |B - C| = |140° - 110°| = 30°
16. ∠BXE = |B - E| = |140° - 30°| = 110°
For numbers 20 and 21, apply the Angle Addition Postulate. This is when you add the individual interior angles to equate to the total angle.
20. ∠PQS = ∠PQR + ∠RQS
112° = 72°+ 10x°
x = 4
21. ∠KLM = ∠KLN + ∠NLM
135° = 47°+ 16y°
y = 5.5
Answer:
4(5)+5y=20 20+5y=20 then subtract the 20 with other 20= 0
5y/5=0/5 y=0
Step-by-step explanation:
ANSWER
D.

EXPLANATION
The given graph rises on the left and falls on the right.
This implies that the degree of the function is even.
Since the graph opens downward, the coefficient of the leading term must be negative.
The graph graph of the function also has 3 intercepts with one of them having an even multiplicity.
This means that the degree must be 4.
Therefore the last choice is correct.
Answer:
A'(2, 6 )
Step-by-step explanation:
Assuming the dilatation is centred at the origin, then multiply each of the coordinates by 
A(3, 9 ) → A'(
(3),
(9) ) → A'(2, 6 )