Question

daca ab+ac=-52 si b+c=-13, calculati a

Answer 1

a · ( b +c )  = - 52 
a · ( -13) = - 52 
a = - 52 : ( -13) 
a = 4 

Answer 2

a x (b+c)= - 52
a x (-13) = - 52
a= -52 : (-13)
a = 4