Cho 6 số thỏa mãn: xa+yb=c ,xb+yc=a, xc+ya=b; abc khác 0 Tính P=

Step-by-step explanation:

xa+yb=c

xb+yc=a

xc+ya=b

add

x(a+b+c)+y(a+b+c)=a+b+c

x+y=1 ... (1)

xac+ybc=c²

xab+yac=a²

xbc+yab=b²

add

x(ab+bc+ca)+y(ab+bc+ca)=a²+b²+c²

75 tickets have been sold so far.

step-by-step explanation:

in this question it is clearly mentioned that 45 children's tickets have been sold and this number is 60% of the total tickets sold.

now let's assume the total number of tickets sold be x.

then 60% of x = 45

⇒

⇒ x(.6) = 45

by dividing with .6 on both the sides of the equation

⇒ x = 75

therefore 75 tickets have been sold so far.

answer: b.48 for

step-by-step explanation: