Respuesta :

Answer:

x = -4, 1

Step-by-step explanation:

Since we have a absolute value function here, we can tell there is goning to be multiple values.

First we will find x with the original function since we know |5| = 5.

Given f(x) = 5 = -2x-3,

[tex]2x-3 = 5 \\

-2x-3+3 = 5 + 3 \\

-2x = 8 \\

x = \frac{8}{ - 2} \\ = - 4[/tex]

Now we also know that |-5| = 5 as well (absolute value)

Given |-2x-3| = |-5|,

[tex] - 2x - 3 = - 5 \\ - 2x - 3 + 3 = - 5 + 3\\ - 2x = - 2 \\ x = \frac{ - 2}{ - 2} \\ = 1[/tex]

You can verifiy these 2 values by substituting them into the equation.

f(-4) = |-2(-4)-3|

= |8-3|

= |5|

= 5

f(1) = |-2(1)-3|

= |-2-3|

= |-5|

= 5

[tex]|-2x-3|=5\\-2x-3=5 \vee -2x-3=-5\\2x=-8 \vee 2x=2\\x=-4 \vee x=1\\\\\boxed{x\in\{-4,1\}}[/tex]