Question

Aflati numerele x,y,z stiins ca sunt direct proportionale cu 3,4,5 si xy+yz+x ori 2 =188

Answer 1

x,y,z direct proportionale 3,4,5
xy+yz+x*2=188
$\frac{x}{3}= \frac{y}{4}= \frac{z}{5}=k$
$\frac{x}{3}= \frac{k}{1}=>x= \frac{3*k}{1}=3k$$\frac{y}{4}= \frac{k}{1}=>y= \frac{4*k}{1}=4k$$\frac{z}{5}= \frac{k}{1}=>z= \frac{5*k}{1}=5k$
x=3k
y=4k
z=5k
3k*4k+4k*5k+3k*2=188
12k+20k+6k=188
38k=188=>k=$\frac{38}{188}$ se simplifica