In triangle RST, angle R =130 degrees and s=1/3 r Find the measures of angle S and angle T.

Answer 1

From the sin law, sin S/s = sin R/r

Thus, as sin S = sin R s/r, sin S = sin R 1/3 r/r = sin R/3, so

S = arcsin(sin R/3) = , in Excel, asin((sin 130°)/3) = 14.79°

T = 180° - 130° - 14.79° = 35.21°.