Answer:
[tex]\displaystyle k = \frac{5}{6}[/tex]
Step-by-step explanation:
We are given the equation:
[tex]\displaystyle (2k+1)x^2 + 2x = 10x - 6[/tex]
And we want to find the value of k such that the equation has two real and equivalent roots.
Since the equation is a quadartic, we can find its discriminant (symbolized by Δ). Recall that:
First, rewrite our equation:
[tex](2k+1)x^2 -8x + 6 =0[/tex]
The discriminant is given by:
[tex]\displaystyle \Delta = b^2 -4ac[/tex]
In this case, b = -8, a = (2k + 1), and c = 6.
Therefore, the discriminant is given by:
[tex]\displaystyle \Delta = (-8)^2 - 4(2k+1)(6)[/tex]
For it to have two equal roots, the discriminant must be zero. Hence:
[tex]\displaystyle 0 = (-8)^2 - 4(2k+1)(6)[/tex]
Solve for k:
[tex]\displaystyle \begin{aligned} \displaystyle 0 &= (-8)^2 - 4(2k+1)(6) \\ 0 &= 64 - 48k - 24 \\ 0 &= 40 - 48k \\ -40 &= -48k \\ \\ k &= \frac{5}{6} \end{aligned}[/tex]
Hence, the value of k is 5/6.
