Please solve #5 and explain how you solved it

Consider that lines b and c are parallel. what is the value of x? what is the measure of the smaller angle?

If m∠abc = 70°, what is m∠abd? justify your reasoning.  using the addition property of equality, 40 + 70 = 110, so m∠abd = 110°.  using the subtraction property of equality, 70 − 30 = 40, so m∠abd = 30°.  using the angle addition postulate, 40 + m∠abd = 70. so, m∠abd = 30° using the subtraction property of equality.  using the angle addition postulate, 40 + 70 = m∠abd. so, m∠abd = 110° using the addition property of equality.

Afurniture store is having a weekend sale and is offering a 20% discount on patio chairs and tables the sales tax on furniture is 6.25%