Answer:
Step-by-step explanation:
<em>#1).</em> It could be good to provide us with the picture, because the answer depends from the angle we choose for letter A.
--- <u><em>If angle A is acute, then m∠A = m∠D</em></u>
and
6x + 12 = 2x + 20 ⇒ x = 2
m∠A = m∠D = 24°
<em>m∠B = m∠C </em>= 180° - 24° = <em>156°</em>
--- <u><em>If angle A is obtuse, then m∠A + m∠D = 180°</em></u>
and
6x + 12 + 2x + 20 = 180 ⇒ x = 18.5
m∠A = <em>m∠B</em> = 6(18.5) + 12 = <em>123°</em>
m∠D = <em>m∠C </em>= 2(18.5) + 20 =<em> 57°</em>
<em>#2).</em> 12k + 5 = 145
12k = 140
k =
=