The equivalent value of the function is x is -3 is -45
Functions are written in terms of variables
Given the function shown
f(x)=-x^2+6x-18
In order to determine f(-3), we will substitute x = -3 into the function to have:
f(-3)=-(-3)^2+6(-3)-18
f(-3) = -9 - 18 - 18
f(-3) = -45
Hence the equivalent value of the function is x is -3 is -45
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