In Las Vegas, Nevada, stores charge a 6.66% state sales tax and a 1.78% county sales tax.
Yuki is purchasing a handbag priced at $220 before tax. How much sales tax does Yuki pay
for her handbag purchase?

1. ∠1 is complementary to ∠2 and ∠3 is complementary to ∠2. subtraction property of equality 2. m∠1 + m∠2 = 90 and m∠3 + m∠2 = 90 substitution 3. m∠1 + m∠2 = m∠3 + m∠2 definition of complementary 4. m∠1 = m∠3 given