Question

daca x; y sunt direct proportionale cu 2;5 si x+y=28 atunci x=.... si y=....

Answer 1

x,y d.p 2,5
x+y=28
x\2=y\5=k
x\2=k⇒x=2k
y\5=k⇒y=5k
2k+5k=28
7k=28
k=28÷7
k=4
x=2×4=8
y=5×4=20

Answer 2

(X,y) d.p. Cu (2,5) = x supra 2= y supra 5 = k
X= 2k; y= 5k
X+y= 28. 2k+5k= 28
7k=28. K=4
X=8 ; y=20