A function is defined as f(x) = 3x - 7.
What is the value of f(4)?
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We have a linear function f of x equals 3x minus 7. We need to find the value of f of 4. This means we substitute x equals 4 into our function. Let's visualize this on a graph where we can see the point at x equals 4.
The first step is to substitute x equals 4 into our function. We replace every x in the expression 3x minus 7 with the value 4. This gives us f of 4 equals 3 times 4 minus 7. Notice how we put parentheses around the 4 to make the substitution clear.
Now we perform the multiplication. We need to calculate 3 times 4, which equals 12. So our expression f of 4 equals 3 times 4 minus 7 becomes f of 4 equals 12 minus 7. The multiplication step is complete.
Finally, we perform the subtraction. We calculate 12 minus 7, which equals 5. Therefore, f of 4 equals 5. On our graph, this corresponds to the point with coordinates 4 comma 5, where x equals 4 and y equals 5. The answer is 5.
To summarize what we learned: Function evaluation requires substituting the given value for x in the expression. We replace x with 4, follow the order of operations by doing multiplication first, then subtraction. The final answer is f of 4 equals 5.