Question

The graph of f(x) = 2x + 3 shifts 10 units to the right when it is replaced with the graph of f(x) = 2x − k. What is the value of k?

A: 3
B: 7
C: 10
D: 13

Answer 1

it's B

Explanation:

Answer 2

k=17

Explanation:

Given F(x)=2x+3 shifts 10 units when it is replaced with the graph f(x)=2x-k.

The method to solve this kind of questions is find where the graph meets the x axis then add ten units to it .The obtained x coordinate is the point where the second graph meets the x axis.

Now first find where the F(x)=2x+3 meets the x axis by substituting F(x)=0.

`2x+3=0`

`x=-(3)/(2)`

Now add 10 to this x coordinate , we get x1=
`10-3/2`=
`17/2`

this is x coordinate where the second line meets the x-axis.

The second line is F(x)=2x-k.

now f(x)=0 and x=17/2

On substitution we get
`0=2*17/2-k`

k=17