Question

18. Find the measure of each numbered angle.

Answer 1

Answer:

m∠1 = 50°, m∠2 = 90°, m∠3 = 40°, and m∠4 = 50°

Step-by-step explanation:

Angles on straight line are equal;

$m \angle1 + 130 = 180$

$m \angle1= 180 - 130 \\ m \angle1= 50$

Vertical angles are equal,

$m \angle4= m \angle \: 1= 50 \degree$

Complementary angles add up to 90°.

$m \angle3 + m \angle4 = 90 \degree \\ 40 + m \angle3 = 90 \degree. \\ m \angle3 = 90 \degree - 50 \degree \\ m \angle3 = 40 \degree$

Angles on straight line adds up to 180°

$m \angle1 + m \angle2 + m \angle3 = 180 \degree$

$40 + m \angle2 + 50 = 180 \\ m \angle2 = 180 - 50 - 40 = 90$