Please help, I will give brainliest.

Suppose that a and b vary inversely and that b=5/2 when a=12. Write a function that models the inverse variation.

b = 15/2a
b = 5/2a
b = 30/a
b = 5/24a

b = 30 / a

which agrees with the third expression in the list of possible options

Step-by-step explanation:

When we say that a and b vary inversely, that means that in mathematical form:

b = k / a  where "k" is the so called "constant of proportionality". In order to write the function that models this inverse variation, we need to find the value of "k". We do such by using the information they provide (b = 5/2 when a = 12):

5/2 = k / 12

Then, solving for "k":

5 * 12 / 2 = k

60 / 2 = k

k = 30

Then we can now write the function that models this inverse variation:

b = k / a

b = 30 / a

exa:

)

3+11

14

step-by-step explanation:

from this example, we can see that subtracting with integers is the same as adding the opposite. we can solve using a number line or by using the saying "keep, change, change" to us solve. it is important to remember that we can subtract a negative and end up with a larger number than we started with.

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