Question

Find the measure of each numbered angle

Answer 1

<1 + <2 =180  it is a straight line

<1 + 57 =180

subtract 57 from both sides

<1=180 -57

<1 = 123 degrees

Answer 2

Answer:

$\angle 1 =123^{\circ}$

Step-by-step explanation:

Given : $\angle 2 = 57$

To Find : $\angle 1 = ?$

Solution:

Linear pair : A linear pair is a pair of adjacent, supplementary angles.

So, $\angle 1 +\angle 2 = 180^{\circ}$

$\angle 1 +57^{\circ}= 180^{\circ}$

$\angle 1 = 180^{\circ}-57^{\circ}$

$\angle 1 = 180^{\circ}-57^{\circ}$

$\angle 1 =123^{\circ}$

Hence $\angle 1 =123^{\circ}$