The product of 3/4 and a number s is 3/5

[10 points, algebra 2]according to my answer key the restrictions are -1 and 4. but why not positive 1?

Using graph paper, determine the line described by the given point and slope. click to show the correct graph below.(0, 0) and 2/3

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?