Answer:
21) x = 0
23) x = 7
Step-by-step explanation:
In a parallelogram, the opposite sides are congruent. Using this fact, we can create equations for both problems.
21)
Subtract 18.
Divide by 2.
23)
Add 3.
No
Let the groups be x and 2x
Its decimal not natual so can't be divided
