<prompt> Pembetatu ABC na ADC ni isosceles na ABBC na ADDC. Pointi D iko ndani ya pembetatu ABC, angle ABC 40circ, na angle ADC 140circ. Ni kipimo gani cha digrii ya angleBAD?  <response>: Kwa sababu pembetatu ABC ni isosceles, pembe BACfrac12displaystyleleft 180circ-angle ABCdisplaystyleright70circ. asyjozi A,B,C,D;A-5,0; B0,21; C5,0; D0,6;choraA--B--C--mzunguko,upana wa mstari1;kuchoraA--D--C--mzunguko,upana wa mstari1;lebo140circ,0,4,S;lebo40circ,0,15,S;leboA,A,W;leboB,B,N;leboC,C,E;leboD,D,N;asy Vile vile, pembe DACfrac12left 180circ-pembeADCkulia20circ. Hivyo angle BAD angle BAC - angle DAC 50circ. 