Question

gasiti a,b,c stiind ca sunt invers proportionale cu :
0,(3),-0,5 ,0,25 , si 6a+2b-5c=50

Answer 1

{a,b,c} i.p.{0,(3); -0,5 ; 0,25} 
a×0,(3)=b×( -0,5)=c×0,25=k
a=k/0,(3)=k/3/9=k/1/3=3k
b= - k/0,5= - k/1/2= -2k
c=k/0,25=k/1/4=4k

6a+2b-5c=50
6×3k+2×( -2k) - 5×4k=50
18k-4k-20k=50
- 6k=50
k=50÷(-6)
k= - 25/3
a=3×( -25/3)= -25
b= -2×(-25/3)=50/3=16,(6)
c= 4×( -25/3)= -100/3= - 33,(3)