find the value of the function y=3x sqr - 21 when x=4

To find the value of the function when x=4, we substitute 4 in place of x in the function:

y = 3(4)^2 - 21
y = 3(16) - 21
y = 48 - 21
y = 27

Therefore, when x=4, the value of the function y is 27.

wrong

I apologize for the mistake. Let me recalculate:

Given function: y = 3x^2 - 21

Substitute x=4 into the function:

y = 3(4)^2 - 21
y = 3(16) - 21
y = 48 - 21
y = 27

Therefore, when x = 4, the value of the function y is 27.