No, it is an irrational number. It repeats
No, it is an irrational number because it does not terminate/end

I'm not sure why ± that sybol isn't working
all together you can write

Ughh just ignore the "A" symbol .-.
Add numbers with the same amount of variables
-x^2 + (-7x^2) = -8x^2
– 28x (+ 14x )= -14x
7 (+ 8) = 15
-18x² - 14x + 15 is your answer
hope this helps
Follow me on insta ashton.3345