3. x = 45
4. 73°
Step-by-step explanation:
3. The sum of the interior angles of a pentagon is 540° so
90° + 112° + 2x + (2x + 10) + 148° = 540°
Simplifying this, we get
4x + 360 = 540 => 4x = 180 or x = 45
4. The sum of the interior angles of a pentagon is 540° which means that the unknown interior angle is 107°. This angle is a supplementary angle to [tex]\angle{A}[/tex] so [tex]\angle{A}[/tex] is
180° - 107° = 73°.
