Karen makes $5 per hour babysitting and $12 per hour giving music lessons. One weekend, she worked a total of 18 hours and mad $139. How many hours did she spend babysitting?

Respuesta :

139=5b+12m 

hope it helped youu!!

she spent 11 hours babysitting and 7 hours giving music lessons. 5 × 11 + 12 × 7 = 139