I don't understand how to do this so please explain or show me how to get the answer
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Answer:
m<ADB=70°
m<ADC=110°
m<DAC=45°
Step-by-step explanation:
<ADB=<ABD(being isosceles triangle: AD=AB)
<ABD+<ADB+<DAB=180°(sum of the angle of triangle is 180°)
2<ADB+40°=180°(<ADB=<ABD and <DAB=40°)
2<ADB=140°
<ADB=70°
<ADB+<ADC=180°(being straight angle)
70°+<ADC=180°
<ADC=110°
<ADC+<ACD+<DAC=180°( sum of the angle of triangle is 180°)
110°+25°+<DAC=180°
<DAC=45°