a function f(x) is defined as f(x)= -8x^2. What is f(-3)?
by now you've probably done it, but watch the "-" signs carefully
f(-3) = -8 * (-3)^2 = -8(9) = -72
All you need to do is substitute -3 in place of the x.
substitute -3 for every x in f(x) and simplify.
To find the value of f(-3), we substitute -3 into the function f(x) and calculate the result.
Given the function f(x) = -8x^2, we substitute x = -3:
f(-3) = -8(-3)^2
First, we evaluate (-3)^2, which means multiplying -3 by itself:
(-3)^2 = (-3) × (-3) = 9
Now, we substitute this result back into the original equation:
f(-3) = -8 × 9
Finally, we simplify the expression by multiplying -8 by 9:
f(-3) = -72
Therefore, f(-3) equals -72.