Data is
Coach tiquet price= 190
First class tiquet price= 990
X= number of coach
Y= first class ticket
People on board trip= 13
Total spent = 6470
Then , equations are
X+ Y = 13
190X + 990Y = 6470
Now find solution, for this 2x2 system
Method of substitution
Substitute Y= 13 - X
190X + 990 (13-X) = 6470
Group in two blocks
190X - 990X = 6470 - 990•13
-800X = - 6400
Then
X= -6400/-800 = 8
Now find Y
Y= 13 - X = 13-8= 5
Then finally answers are
She buyed 5 first class tickets
and 8 c