A relation contains the ordered pairs shown. One of the ordered pairs is missing an x-coordinate. {(-1, 4), (0, 4), (2, 5), (3, -6), (?, 7)}
What could be the missing x-coordinate if the relation is a function?
A. 0
B. 2
C. 8
D. -1

Could someone me with this question i’ve been stuck on it for 20 minutes

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?

Graph the line y=4/3 x+1 . use the line tool and select two points on the line.