Question

What is the domain of the function: {(1, 2); (2, 4); (3, 6); (4, 8)}?


A.
{6, 8}


B.
{2, 4, 6, 8}


C.
{1, 2, 3, 4, 6, 8}


D.
{1, 2, 3, 4}

What is the range of the function: {(2, 1); (4, 2); (6, 3); (8, 4)}?


A.


{2, 4, 6, 8}


B.


{1, 2, 3, 4}


C.


{1, 2, 3, 4, 6, 8}


D.


{6, 8}


Suppose p varies directly with d, and p = 7 when d = 3. What is the value of d when p = 28?



A.4/3




B.140/3




C.
16


D.
12

Answer 1

Domain - List all the inputs y=f(x) where x is the input

Range - List all the resulting outputs, y=f(x) , y is the output

in the set of points (x,y)

Answer 2

If p varies directly with d, then it is directly proportional , you can say...

p = some constant x d

p = k*d

use given p and d, solve for the constant k value to get your expression

Answer 3

ok i'll try that out

Answer 4

where are you getting the k from?

Answer 5

it is a proportion constant, varies directly in general is y=k*x, linear

Answer 6

\[y~ \alpha~ x\]

y=k*x