Question

Solve the problems. Write the complete proof in your homework and for online (only) respond to questions or statements (if any) that are parts of your proof or related to it.

Answer 1

Step-by-step explanation:

Well we know that ZACB=LABC because

AABC is isosceles, so base angles theorem applies.

m<ACB=70°

So mzDCE=m/DEC-35° because of base angles theorem, and because mzDCE=m/ACB-m<ECB=70°-35°

Finally, DE || CB because the alternate interior angles ECB=<DEC