SOLUTION: If f(x) = 3x^2 - Bx + 4, and f(-1) = 12, what is the value of B? Let me give it a try. Let x = -1 and f(-1) be 12. 3(-1)^2 - B(-1) + 4 12 = 3(-1)^2 -B(-1) + 4

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Question 1208026: If f(x) = 3x^2 - Bx + 4, and f(-1) = 12, what is the value of B?

Let me give it a try.

Let x = -1 and f(-1) be 12.

3(-1)^2 - B(-1) + 4

12 = 3(-1)^2 -B(-1) + 4

12 = 3(1) + B + 4

12 = 3 + B + 4

12 = B + 7

12 - 7 = B

5 = B

You say?


Found 2 solutions by josgarithmetic, ikleyn:
Answer by josgarithmetic(39617)   (Show Source): You can put this solution on YOUR website!
means that the point (-1,12) is a point on the function f.

Use that known point for x and f(x).



----------and could have been done in one or two fewer steps.

Answer by ikleyn(52781)   (Show Source): You can put this solution on YOUR website!
.

Your solution is good, correct and perfect.

My congratulations - you did a perfect job !



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