Question

daca ab+ac=725 si b+c=29 ,sa se calculeze:
a) 6b+6c
b)3a-63

Answer 1

a) 6b+6c=6x(b+c)=6x29=174
b) a*(b+c)=725
a*29=725
a=25

3a-63= 3 x 25- 63 =75-63= 12.

Answer 2

 ab+ac=725 ⇒a(b+c)=725  (1)

                      si b+c=29    (2)

din (1) si (2) ⇒⇒a=725:(b+c)=725:29=25⇒a=25

a) 6b+6c=6(b+c)=6×29=174

b)  3a-63=3×25-63=75-63=12