tan30=√3/3=x/50 +x
51x/50=√3/3
x=(√3/3)*(50/51)=50√3/153tan30°=x/（50+x）tan30=√3/3=x/(50 +x)√3(50-x)=3x50√3=(3+√3)xx=50√3 /(3+√3)=50/(1+√3)=50/2.732= 18.301650+x怎么变50-x 了tan30=√3/3=x/(50 +x)√3(50+x)=3x50√3=(3-√3)xx=50√3 /(3-√3)=50/(√3-1)=50/0.732= 68.306马虎，马虎