Question

a+b=21 a÷b=4rest 1 va rog frumos

Answer 1

a \ b = 4 rest 1 => a = b x 4 + 1

Inlocuim in prima egalitate =>

b x 4 + 1 + b = 21
b x 5 = 21 - 1
b x 5 = 20
b = 20 \ 5
b = 4
=> a = 21 -b = 21 - 4 = 17
a = 17
b = 4

Sper ca te-am putut ajuta !
Spor !

Answer 2

$a+b=21 \\ a:b=4 \ r \ 1 \to \boxed{a=4b+1} \\ \\ 4b+1+b=21 \\ \\ 5b+1=21 \\ \\ 5b=20 \\ \\ \boxed{b=4} \\ \\ a+4=21 \\ \\ a=21-4 \\ \\ \boxed{a=17}$