Would the domain of this function be all real numbers or integers(positive or negative whole numbers)

Which of the following parabolas opens up?

Hich equation can pair with x + 2y = 5 to create an inconsistent system? 2x + 4y = 3 5x + 2y = 3 6x + 12y = 30 3x + 4y = 8

Add, subtract, multiply, or divide as indicated. list any restrictions for the variable(s) and simplify the answers when possible. 1) x-2 / x+5 + 3x / 2x-1 2) x+6 / x-6 - x^2 / x+6 3) x+9 / x-4 + x+2 / x^2-11x+28 4) x / x^2-64 + 11 / 2x^2+11x-40 5) 5 / x + 11 / x-3 - x-4 / x^2+2x-15