What is the common ratio of the sequence? -2, 6, -18, 54,...
a.-3
b.-2
c.3
d.8

The $x$-intercepts of the parabola $y = x^2 + bx + c$ are $(-3,0)$ and $(5,0).$ find the equation of the parabola, and submit your answer in $y = ax^2 + bx + c$ form.

Equation for the calculation double 2 and then add 5

I'm confused on this could anyone me and show me what i need to do to solve it.