recall in a perfect square trinomial, the middle term is the tale-tell guy, we know the middle term is the product of 2 and the two other guys without the exponent, so in this case 6x = 2*√x² * √c.

I got:
c) 18x-9=72
d) 3(6x-3)=72
e) x=4.5
If you need any explanations for the answers, please tell me!
Answer:
3
Step-by-step explanation:
9/14 stays the same
2/7 turns into 4/14
1/ into 7/14
all of them added is 20/14
simplified is 1 3/7