Find the value of the function y=3x2−21 when x=4 .(1 point) y= .
To find the value of the function y = 3x^2 - 21 when x = 4, we substitute x = 4 into the equation:
y = 3(4)^2 - 21
y = 3(16) - 21
y = 48 - 21
y = 27
Therefore, when x = 4, y = 27.