If f(x) = 2x + 3, f(4) = ?

**The reasoning** This is about **function evaluation** — simply substitute the given value into the function. Given: f(x) = 2x + 3, and we need f(4) Replace every "x" with 4: - f(4) = 2(4) + 3 - f(4) = 8 + 3 - f(4) = **11** Think of a function as a machine: you feed it a number (input), it follows its rule, and gives you back an answer (output). Here, the rule is "multiply by 2, then add 3." **Why the wrong options tempt you** - **A) 8** — You stopped after 2(4) and forgot to add 3. The function has *two* operations! - **C) 14** — You might have added incorrectly (2+4+3 = 9, not 14) or multiplied 2×4 then doubled it somehow. Stay organized! - **D) 20** — Perhaps you did 4×3 + 8, mixing up the operations. Always follow BODMAS strictly. **Quick takeaway** Function notation f(x) means "what you do *to* x" — so f(4) means do everything in the formula *to* 4, step by step. Substitute, then calculate carefully!