Answer:
A.
Step-by-step explanation:
when you plot the vertices;
Side AB is perpendicular to side BC
Side AB is parallel to side DC
Side AC is perpendicular to AB
Side AC is perpendicular to DC
Side AC is parallel to side BC
The conclusion made is that ABCD is a rectangle
Step-by-step
=> 900=-100x+300
=> -100x+300=900
=> -100x=900–300
=> -100x=600 divide both side by -100
=> x=-6
Your answer would be 6 cm
To get the improper fraction of 10 5/12, multiply the denominator of the fraction and the number on the left which is 10x12=120.
Then you want to add the numerator 5 to 120 to get 125.
Using the denominator 12, and the numerator 125, there is your answer. 125/12.
Hope it wasn't too confusing..
Hope this helped :)