+0  
 
0
26
2
avatar

Can someone help  △EDC is similar to △ABC. Solve for x.

 

 

 

△ABC is similar to △DEF.

Guest Sep 9, 2018
 #1
avatar+7266 
0

 

△EDC  is similar to  △ABC ,  so side  DC  corresponds to side  BC .

 

Let the scale factor from  △EDC  to  △ABC  be  s .

 

DC * s   =   BC

 

4 * s   =   6

 

s   =   6/4

 

s   =   1.5

 

So each side of  △ABC  is  1.5  times the corresponding side of  △EDC.

 

EDC  is similar to  △ABC ,  so side  EC  corresponds to side  AC .

 

EC * 1.5   =   AC

 

And we can see from the picture that   EC  =  x   and   AC  =  12.5 - x  , so....

 

x * 1.5   =   12.5 - x

 

1.5x   =   12.5 - x

                                 Add  x  to both sides of the equation.

1.5x + x   =   12.5

 

2.5x   =   12.5

                                 Divide both sides by  2.5 .

x   =   5

hectictar  Sep 10, 2018
 #2
avatar+7266 
0

The sum of the angles in every triangle is  180° , so..

 

∠A + ∠B + ∠C   =   180°

 

21° + 90° + ∠C   =   180°

 

∠C   =   180° - 21° - 90°

 

∠C   =  69°

 

∠D  corresponds to  ∠A  so...

 

∠D   =   ∠A   =   21°

 

∠F  corresponds to  ∠C  so...

 

∠F  =  ∠C  =  69°

hectictar  Sep 10, 2018

10 Online Users

avatar
avatar
avatar

New Privacy Policy

We use cookies to personalise content and advertisements and to analyse access to our website. Furthermore, our partners for online advertising receive information about your use of our website.
For more information: our cookie policy and privacy policy.