First, let's clarify the functions given in the problem.
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The price of the first stock is modeled by the function: \[ f(x) = 0.75x^2 - 6x + 20 \]
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The price of the second stock is given as: \[ g(x) = 2.75 + 1.50 \] This simplifies to: \[ g(x) = 4.25 \]
We need to find out when \( f(x) = g(x) \), which translates to solving the equation: \[ 0.75x^2 - 6x + 20 = 4.25 \]
Subtract \( 4.25 \) from both sides: \[ 0.75x^2 - 6x + 20 - 4.25 = 0 \] \[ 0.75x^2 - 6x + 15.75 = 0 \]
Next, we can multiply the entire equation by 4 to eliminate the decimal: \[ 3x^2 - 24x + 63 = 0 \]
Now let's solve this quadratic equation using the quadratic formula: \[ x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \] where \( a = 3 \), \( b = -24 \), and \( c = 63 \).
First, calculate the discriminant \( b^2 - 4ac \): \[ b^2 = (-24)^2 = 576 \] \[ 4ac = 4 \cdot 3 \cdot 63 = 756 \] \[ b^2 - 4ac = 576 - 756 = -180 \]
Since the discriminant is negative (\(-180\)), this indicates that the quadratic equation has no real solutions.
As a result, the graphs of \( f(x) \) and \( g(x) \) do not intersect.
Therefore, the answer to how many times during the 6-month period will both stocks be at the same price is: 3) never.