so1963
Answered

What is the length of x? What is the length of EF? Only enter numbers in the answer boxes below:

What is the length of x? What is the length of EF? Only enter numbers in the answer boxes below: class=

Answer :

Focus on triangles DFC and DFE:

  • They are both right triangles because DF is perpendicular to EC
  • DC=DE
  • DF is a common side

So, the two triangles are congruent. It follows that CF=FE, and in particular

[tex]8x=3x+15 \iff 5x=15 \iff x=3[/tex]

And since x=3, the length of EF is

[tex]EF=3x+15=3\cdot 3+15=24[/tex]

Other Questions