Pls help 15 points question
Answers
2. BP is the angle bisector of angle ABC,
So angle ABP = angle CBP
DQ is the angle bisector of angle CDA,
So angle CDQ = angle ADQ
In ΔADQ,
ADQ + AQD + DAQ = 180
⇒ 0.5 ADC+ Q + A = 180 -----------------(1)
In ΔCBP
CBP + CPB + BCP = 180
⇒ 0.5 CBA + P + C = 180 ------------------(2)
adding (1) and (2);
0.5 ADC+ Q + A + 0.5 CBA + P + C = 180+180
⇒ C + A + 0.5 ABC + 0.5 ADC + P + Q = 360 ---------------(3)
we know that sum of all angles of a quadrilateral = 360
or A+C+ ABC + ADC = 360 ----------------------(4)
from (3) and (4)
A+C+ ABC + ADC = C + A + 0.5 ABC + 0.5 ADC + P + Q
⇒ ABC + ADC = 0.5 ABC + 0.5 ADC + P + Q
⇒ P + Q = ABC - 0.5 ABC + ADC - 0.5 ADC
⇒ P+Q = 0.5 ABC + 0.5 ADC
⇒ P+Q = 0.5(ABC + ADC)
3.In triangle PQM
=> PMQ + MPQ + Q = 180 [Angle sum property of a triangle]
=> 90 + MPQ + Q = 180 (PMQ = 90)
=> Q = 90 - MPQ
=> 90 - MPQ = Q _____(1)
In triangle PMR
=> PMR + PRM + R = 180
=> 90 + MPR + R = 180
=> R = 90 - MPR
=> 90 - MPR = R _____(2)
Subtracting (1) and (2), we get
=> (90 - MPQ) - (90 - MPR) = Q - R
=> MPR - MPQ = Q - R
=> (RPA +APM) - (QPA - APM) = Q - R
=> QPA + APM -QPA + APM = Q - R [ As PA is bisector of QPR so, RPA=QPA]
=> 2 APM = Q - R
=> APM = 1/2 (Q - R)
Answer:
refer to the attachment above for ur answer
hope it helps you ^_^