AB=BC and BC=CD, AB=3x−1 and CD=2x+3

Prove: BC=11

1. what is the measure of ∠abc? what is the measure of ∠abd?

Express in the simplest form: (x^2+9x+14/x^2-49) / (3x+6/x^2+x-56)

Select the correct answer. what is the exact value of sin (157.5°)? a. 'sqrt(2 - sqrt(2))/2 b. *"-"'sqrt(2 + sqrt(2))/29 c.'sqrt(2 + sqrt(2))/4" d. "-"sqrt(2 + sqrt(2))/4)