Help pls i don’t know why my teacher is giving us these questions (middle school btw)

The equation x2 – 1x – 90 = 0 has solutions {a, b}. what is a + b?

If you double the input of a function and it results in half the output, and if you triple the input and it results in a third of the output, what can be guessed about the function? check all that apply.

What is 617.3 miles and each gallon of gas the car can travel 41 miles select a reasonable estimate of the number of gallons of gas karl used.