Explicație pas cu pas:
(x,y,z) D.P (3,5,9)=>
=>x/3=y/5=z/9=k
"k"-raport de proporționalitatea.
x/3=k=>x=3k
y/5=>y=5k
z/9=k=>z=9k
x²+y²+z²=1035=>(3k)²+(5k)²+(9k)²=1035=>9k²+25k²+81k²=1035=>34k²+81k²=1035=>115k²=1035=>k²=1035÷115=>k²=9=>k=√9=3=>k=3
x=3k=3×3=9=>x=9
y=5k=5×3=15=>y=15
z=9×3=27=>z=27
Baftă!
