Answer:
a quantity representing the power to which a given number or expression is to be raised, usually expressed as a raised symbol beside the number or expression
Step-by-step explanation:
A tip would be to watch a video on exponents and pemdas, they can be really helpful!
Hope this helps!
Answer: x=2 because for any y value the x value is always 2.
Answer: 
Step-by-step explanation:

Subtract 20x

add 15

Combine like terms

Divide by -25 (NOTE: When dividing or multiplying by negative numbers the inequality sign flips.)

I believe that the answer is B
I hope this helps. :)
3(x-1)=2x+5
3x-3=2x+5
3x-2x=3+5
x=8