Find the value of c such that the point (2, 5) lies on the graph of
f(x) = cx^2 + 4x − 2.

c=????

Question

Find the value of c such that the point (2, 5) lies on the graph of
f(x) = cx^2 + 4x − 2.

c=????

tkhunny · Answer

Have you considered substituting the give values?  x = 2, y = 5

marigirl · Answer

Yes write it as
5=c(2)^2+4(2)-2 and then solve for c.

anonymous · Answer

Would the answer be -5?

anonymous · Answer

-1/4?

whpalmer4 · Answer

Let's find out!

$$f(x) = -5x^2+4x-2$$$$f(2) = 5 = -5(2)^2+4(2)-2$$$$5 = -5(4) + 4(2) - 2$$$$5 = -20 +8 -2$$Is that true?

whpalmer4 · Answer

Let's find out:
$$5 = -\frac{1}{4}(2)^2+4(2) - 2$$$$5 = -1+8-2$$$$5 = 5\checkmark$$

anonymous · Answer

awesome! people are so helpful here

whpalmer4 · Answer

You should go back and figure out what mistake you made that made you think $c=-5$...
learn from your mistakes!