30 Points And I will give you brainlist I NEED HELP

Consider the table below. x y -1 -5 0 5 1 11 2 13 3 11 complete the standard form equation representing the quadratic relationship displayed above, where a, b, and c are constants.

Aclassmate thinks that solving a system by graphing gives an exact answer when the lines appear to cross at a grid point, but only an approximate answer when they don't. explain why this isn't true.

Shannon mary and john earn a weekly allowance ahannon earns the amount that is 2/3 of what john earns mary earns an amount that is 1 2/3 of what johns earns 20 dollars a week who eaens the greatest allowance and who earns the least