Question

What does arc ABC equal?

Answer 1

Answer: 270°

Explanation:

Method 1:

`\stackrel{\frown}{AB}+\stackrel{\frown}{BC}+\stackrel{\frown}{CA}\ =360\\\\146\ +\stackrel{\frown}{BC}+\ 90\ =360\\\\.\qquad 236\ +\stackrel{\frown}{BC}\ =360\\\\.\qquad \qquad \stackrel{\frown}{BC}\ =124\\\\\\\stackrel{\frown}{ABC}\ =\ \stackrel{\frown}{AB}+\stackrel{\frown}{BC}\\\\.\qquad=146+124\\\\.\qquad=270`

Method 2:

`\stackrel{\frown}{ABC}+\stackrel{\frown}{CA}\ =360\\\\\stackrel{\frown}{ABC}\ +\ 90\ = 360\\\\\stackrel{\frown}{ABC}\ =\ 270`