Question

F(x)=x^2, g(x) =6x+4
Which value of x does (f+g)(x)=0

Answer 1

Answer:

Step-by-step explanation:

It seems to me that you are being asked for what values of x does f(x) + g(x) = 0. Which means that you need to add them together, combine like terms if possible, and then factor. Adding them together gives you

$x^2+6x+4=0$  This doesn't factor to integer solutions, so we will use the quadratic formula to factor it. The quadratic formula is as follows:

$x=\frac{-b+-\sqrt{b^2-4ac} }{2a}$ For us, a = 1, b = 6, c = 4. Filling in accordingly:

$x=\frac{-6+-\sqrt{36-4(1)(4)} }{2}$ and simplifying a bit:

$x=\frac{-6+-\sqrt{20} }{2}$  The square root of 20 can be simplified down to 2√5, so plugging that in gives us:

$x=\frac{-6+-2\sqrt{5} }{2}$ and then reducing everything down to its lowest terms:

x = -3 ± √5. Those are irrational numbers but they are the numbers that make that addition o to 0.