Question

数学七年级下册三角形的外角的一道题,有图

Answer 1

(1)∠A=180-∠B-∠C

∠P=180-1/2∠B-1/2∠C=90+1/2(180-∠B-∠C)=90+1/2∠A

(2)∠A=180-∠B-∠C

∠P=180-1/2∠B-[∠C+1/2(180-∠C)]=90-1/2∠B-1/2∠C=1/2∠A

(3)∠A=180-∠B-∠C

∠P=180-1/2(180-∠B)-1/2(180-∠C)=1/2(∠B+∠C)=1/2(180-∠A)=90-1/2∠A