Răspuns:
Explicație pas cu pas:
[tex]\dfrac{a+2}{2} =\dfrac{b+3}{3}=\dfrac{c+4}{4}=\dfrac{d+5}{5},~~si~~3a+b+d=40.\\Amplificam~prima~fractie~cu~3,~=>~\\\dfrac{3a+6}{6} =\dfrac{b+3}{3}=\dfrac{d+5}{5}=\dfrac{3a+6+b+3+d+5}{6+3+5}=\dfrac{40+14}{14}=\dfrac{54}{14}=\dfrac{27}{7}.\\=>~\dfrac{a+2}{2} =\dfrac{27}{7}~=> ~7(a+2)=2*27~=>~7a+14=54~=>~7a=40~=>~a=\dfrac{40}{7} \\=>~\dfrac{b+3}{3} =\dfrac{27}{7}~=> ~7(b+3)=3*27~=>~7b+21=81~=>~7b=60~=>~b=\dfrac{60}{7} \\[/tex]
[tex]=>~\dfrac{c+4}{4} =\dfrac{27}{7}~=> ~7(c+4)=4*27~=>~7c+28=108~=>~7c=80~=>~c=\dfrac{80}{7}\\ =>~\dfrac{d+5}{5} =\dfrac{27}{7}~=> ~7(d+5)=5*27~=>~7d+35=135~=>~7d=100~=>~d=\dfrac{100}{7} \\[/tex]