Troy signed up for a new cell phone plan which charges him a fee of $40 per month, plus $0.05 for each text message ( t) that he sends. if troy wants to spend at most $70 on his cell phone bill this month, which inequality below can be used to determine the number of text messages that he can send?

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?