Please help with some of these, I don’t have a clue on what to do. Please explain step by step if possible or like you would explain it to a 5 year old.

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.

What is the value of x in the diagram below?

Angle 1 and 2 are a linear pair. angle 1 equals x-39 and angle 2 equals x+61 . find the measure of each angle