a + b = 30
[tex]a= \frac{1}{4}b[/tex]
[tex]\frac{b}{4} + b = 30[/tex]
[tex]\frac{b}{4} + \frac{4b}{4} = \frac{120}{4} |*4[/tex]
[tex]b+4b=120[/tex]
[tex]5b=120[/tex]
[tex]b= \frac{120}{5} [/tex]
[tex]b=24[/tex]
a + 24 = 30
a = 30 - 24
a = 6
Proba 6 + 24 = 30
