Find $$ f(-3) $$ when $$ f(x)=5 x^{2}-3 x-7 $$. A. 61 B. 29 C. 11 D. 47

Question

UpStudy AI · Accepted Answer

We are given the function 
$$
f(x)=5x^2-3x-7.
$$
To find $$ f(-3) $$, substitute $$ x=-3 $$ into the function:
$$
f(-3)=5(-3)^2-3(-3)-7.
$$

**Step 1:** Calculate the square:
$$
(-3)^2=9.
$$

**Step 2:** Multiply by 5:
$$
5 \times 9=45.
$$

**Step 3:** Multiply $$-3$$ and $$-3$$:
$$
-3 \times (-3)=9.
$$

**Step 4:** Combine the results:
$$
f(-3)=45+9-7.
$$

**Step 5:** Perform the addition and subtraction:
$$
45+9=54,
$$
$$
54-7=47.
$$

Thus, 
$$
f(-3)=47.
$$

The correct answer is D. 47.
$$ f(-3) = 47 $$, so the answer is D. 47.

Find \( f(-3) \) when \( f(x)=5 x^{2}-3 x-7 \). A. 61 B. 29 C. 11 D. 47