Answer:
2 is a number and "twice a number" means multiply by 2.
Symmetrical because the numbers in a bar graph show sort of a pyramid-like shape, rather than a skewed or flatter shape.
Use Pythagorean theorem:
9i-j = sqrt (9^2 - 1^2) = sqrt(81-1) = sqrt80
now divide both terms in V by that:
u = 9/sqrt(80)i - 1/sqrt(80)j
see attached picture:
ANSWER
Three (3) cartons of juice
Y=3X+68.25
80=3X+68.25
Subtract 68.25 from both sides
11.75=3X
Divide
11.75/3=3.91
He can't buy a portion of a juice but he doesn't have enough to buy 4
So he can afford 3 juice cartons