Calculate the area of triangle ABC, if given by alpha = 49°, beta = 31°, and the height on the c side is 9cm.

Correct answer:

S =  102.6094 cm2

Step-by-step explanation:

α=49 β=31 h=9 cm  tanα=h:c1 c1=h/tanα=h/tan49 =9/tan49 =9/1.150368=7.82358 cm  tanβ=h:c2 c2=h/tanβ=h/tan31 =9/tan31 =9/0.600861=14.97852 cm  c=c1+c2=7.8236+14.978522.8021 cm  S=c h2=22.8021 92=102.6094 cm2

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