Question

se stie ca a*b+a*c=25 nr a este 5, iar nr b este impatritul lui ce afla nr b si c

Answer 1

a*b+a*c = 25
a = 5
a(b+c) = 25
5(a+b) = 25
b+c = 25:5
b+c = 5
b = 4*c
4c+c = 5
5c = 5
c = 5:5
c = 1
b = 4*c
b = 4*1
b = 4

Answer 2

$ab+ac=25 \\ a=5 \\ b=4c \\ a(b+c)=25 \\ 5(b+c)=25 \\ b+c=25:5 \\ b+c=5 \\ 4c+c=5 \\ 5c=5 \\ c=5:5 \\ \boxed{c=1} \\ b=4c \\ b=4 \cdot 1 \\ \boxed{b=4}$