Find the value of the quadratic expression $3x^2$3x2 for each of the following $x$x-values.
$x=5$x=5
$x=-5$x=−5
Find the value of the quadratic expression $3x^2+1$3x2+1 when $x=1$x=1.
Find the value of the following quadratic expression when $x=7$x=7.
$4x+5x^2$4x+5x2Find the value of the following quadratic expression when $x=8$x=8.
$6x^2+5x-4$6x2+5x−4