Respuesta :

msm555

Answer:

Solution given:

<A=49°

<B=90°

angle ECD=?

we have

<A+<B+<C=180°[sum of interior angle of a triangle is 180°

<A+40+90=180°

<A=180°-130°

<A=50°

wehave

<A=<ECD[vertically opposite angle]

:.angle ECD=50°.