Determine whether y varies directly with x. If so, find the constant of variation k write the equation

It varies directly

k =

Step-by-step explanation:

Table:

    x      y

   7       11

   8       13

   9       15

   10      17

Problem:, determine if y varies directly as x

Solution:

  The equation to determine if they vary directly is;

         y ∝  x

         y  = kx

From the table, y varies directly as x. As y increases, x also increases.

To find k, use any convenient value of y and x  ;

     y  = 15 and x  = 9;

        15 = k x 9

        k =  =

-13

step-by-step explanation:

f(x)=2x-5 for f(-4)

f(-4)   means let x=-4

f(-4) = 2(-4) -5

f(-4) =-8-5

      = -13

312312

step-by-step explanation: