Question Type: Quadratic Equations
Step-by-step solution:
If two quadratic equations have both roots common, then the ratio of the corresponding coefficients must be equal.
Let the quadratic equations be:
\(2x^2 + Kx + 8 = 0\) ...(1)
\(3x^2 + 4x + 12 = 0\) ...(2)
For both equations to have common roots, the ratio of their corresponding coefficients must be equal. Therefore:
\(\frac{2}{3} = \frac{K}{4} = \frac{8}{12}\)
We can use any two ratios to solve for K. Let's use the first and third ratios:
\(\frac{2}{3} = \frac{8}{12}\)
This simplifies to \(\frac{2}{3} = \frac{2}{3}\), which is true, confirming that the equations could potentially have common roots.
Now let's use the first and second ratios to solve for K:
\(\frac{2}{3} = \frac{K}{4}\)
Cross-multiplying, we get:
\(2 \times 4 = 3 \times K\)
\(8 = 3K\)
\(K = \frac{8}{3}\)
Therefore, the value of K is \(\frac{8}{3}\).
Eliminating Incorrect Options:
What number should be subtracted from x3−4x2−8x+11 to make the number divisible by (x+2)?