An airplane descends from an altitude of 32,000 feet above sea level to an altitude of 27,000 feet above sea level. what is the change in altitude?

The two square pyramids are similar. find the total volume of both pyramids if the ratio of their surface areas is 9/16

Factor the trinomial below. 12x^2 - 32x - 12 a. 4(3x+3)(x-1) b. 4(3x+1)(x-3) c. 4(3x+6)(x-2) d. 4(3x+2)(x-6)

Statements reasons 1. ab ? cd; ad ? bc 1. given 2. ac ? ac 2. reflexive property 3. ? adc ? ? cba 3. ? 4. ? dac ? ? bca; ? acd ? ? cab 4. cpctc 5. ? dac and ? bca are alt. int. ? s; ? acd and ? cab are alt. int. ? s 5. definition of alternate interior angles 6. ab ? cd; ad ? bc 6. converse of the alternate interior angles theorem 7. abcd is a parallelogram 7. definition of parallelogram what is the missing reason in step 3?