If y varies directly with x and y = 25 when x = 5, what is the value of k? how does this work when y = kx?

The value of k when x=5 and y=25 is:

                              k=5

Direct variation--

Two variables are said to be in direct variation if one variable could be written as a constant multiple of the other variable.

i.e. x and y are said to be in direct variation.

if there exist a constant k such that:

or if x is non-zero then we have:

Here we are given x=5 and y=25

This means that the value of k is:

the transverse axis of a hyperbola is the line that contains the two vertices and the two focuses.

in this example (hyperbola of equation x^2/2 - y^2/4 = 1), the transverse axis is the  x-axis  . 

step-by-step explanation:

for this pair of functions g(x)=x-2 and f(x)=|x| is (g o f)(a)= |a| -2

step-by-step explanation:

g(x)=x-2

f(x)=|x|

(g o f)(a)=?

(g o f)(x)=g(f(x))

(g o f)(x)=g(|x|)

(g o f)(x)=|x|-2

(g o f)(a)=|a|-2