The plot below represents the function f(2): 4
3
2
1
5 4 3 2 1
Evaluate f (4):
f14)
41
X
Solve f(x) = 4:
ONE
Question Help D Video Message instructor D Pos
Stanit Question

f(4) = 3

x = -1

Step-by-step explanation:

Line graphed shows a linear function.

Since this line passes through two points (4, 3) and (-1, 4)

Let the function is,

f(x) = mx + b

where 'm' = slope of the line

b = y-intercept of the line

Slope 'm' =

               =

               =

f(x) =

Since a point (4, 3) lies on the line,

f(4) =

3 =

b = 3 + 0.8

b = 3.8

Therefore, f(x) = -0.2x + 3.8

For x = 4

f(4) = -0.2(4) + 3.8    

     = -0.8 + 3.8

     = 3.0

For f(x) = 4

4 = -0.2x + 3.8

0.2x = 3.8 - 4

x =

x = -1

if you are saying purchasing 3 social media ads and one newspaper ad counts as one purchase then there are:

6 purchases

if you are asking how many of each then:

18 social media ads

6 newspaper ads