Iknow it's a lot but bear with me. i need to do this for hw, but i don't understand

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

Full year - williamshow many square inches are in 60 square feet? 5 square inches72 square inches720 square inche8.640 square inches

What are the solutions for the following system? -2x^2+y=-5 y=-3x^2+5