Respuesta :

Answer:

EF is 16.  

Step-by-step explanation:

So we know that Point E is somewhere on Line DF. In other words, DE plus EF must equal DF. In an equation, this is:

[tex]DF=DE+EF[/tex]

We are given that DE is 2x, EF is 2x-6, and DF is 3x+5. So, substitute:

[tex](3x+5)=(2x)+(2x-6)[/tex]

Now, solve for x.

On the right, combine like terms:

[tex]3x+5=4x-6[/tex]

Subtract 4x from both sides:

[tex]-x+5=-6[/tex]

Subtract 5 from both sides:

[tex]-x=-11[/tex]

Divide both sides by -1:

[tex]x=11[/tex]

Now that we know x is 11, substitute this back into the equation for EF to find EF.

[tex]EF=2x-6[/tex]

Substitute 11 for x:

[tex]EF=2(11)-6[/tex]

Multiply:

[tex]EF=22-6[/tex]

Subtract:

[tex]EF=16[/tex]

And we're done!