Question

Given F(x) = 3x^2 - 4 and F(a) = 8, find a.

Answer choices are

plus or minus 2

4

188

Answer 1

@zepdrix

Answer 2

\[\large\rm F(\color{orangered}{x})=3(\color{orangered}{x})^2-4\]And they told us that when we plug a into the equation,\[\large\rm F(\color{orangered}{a})=3(\color{orangered}{a})^2-4\]the result (or output) is 8,\[\large\rm 8=3(\color{orangered}{a})^2-4\]

Answer 3

So you'll have to apply a few algebra steps to `isolate` your a.

Answer 4

There's a 4 being subtracted... hmmm
so maybe adding 4 to each side would be a good step, ya?

Answer 5

oh okay! I'm gonna try this one by myself then! thank you!