Question
One of the roots of the equation x^2 +4x = \frac{2k+1}{2} is three times the other root. Find the value of k. (4 marks)
Answer
Hi weiling, apologies for the late reply, for this question the first step we need to do is move \frac{2k+1}{2} to the LHS of the equation so that the RHS is 0 and we get a quadratic equation in the form of ax^2 + bx +c=0.
x^2 +4x - \frac{2k+1}{2}=0
Since one of the roots is 3 times the other root, we can let our root be \alpha, 3\alpha (basically you can use any symbol but x or k)
Here’s another similar method that will lead to the same answer:
Hope this helps! 