Matthew paid $5 for 8 toothbrushes. jon paid $18 for 25 toothbrushes. find the unit cost to determine how much each person paid per toothbrush.

Matthew payed .63 (rounded .625) cents for each toothbrush while Jon payed .72 cents per toothbrush

Step-by-step explanation:

$5 = 8 toothbrushes

$18 = 25 toothbrushes

5 / 8 = .625

18/25 = .72

hello from mrbilldoesmath!

answer:

(7 x + 6 y) (49 x^2 - 42 x y + 36 y^2)

discussion:

the trick is to recognize that 343 = 7^3 and 216 = 6^3 and, in general,

a^3 + b^3 =   (a + b) (a^2 - a b + b^2).

in our case

343x^3+216y^3   =   (7x)^3 + (6y)^3

so take a = 7x and b = 6y in the above equation to get the answer.

you,

mrb