Ex 3, cel cu unghiuri complementare!

Răspuns:
unghiuri complementare=suma de 90 de grade
A+B=90
A+(1/5×A+27)=90 |•5
5A+A+27×5=90×5
6A+135=450|-135
6A=450-135
6A=315
A=315÷6= 52⁰30'
B=90-52⁰30'=37⁰30'