a.) A= (1/2)absinC b.) sinA/a, sinB/b, sinC/c sin100/42, sin25/b, sinC/c use these two fractions. sin100/42= sin25/b cross multiply next b×sin100= 42×sin25 then divide on both sides by sin100 b=18 c.)measurementofA+measurementofB+measurementofC=180 100+25+C=180 125+C=180 -125 -125 The measurement of angle C is 55 degrees. d.)A=(1/2)42×18×sin55 = 21×18×sin55 A =309.6 units squared
