Respuesta :
Answer:
x² + kx + 9 = 0
To find the possible values of k first calculate the discriminant D
D = b² - 4ac
where
a = 1 b = k and c = 9
D = k ² - 4(1)(9)
D = k² - 36
For the above equation to have one solution D must be equal to zero
That's
D = 0
We get
k² - 36 = 0
(k+6)(k -6) = 0
k = 6 k = - 6
Therefore the two values of k which make
x² + kx + 9 have only one solution is
6 and - 6
Hope this helps.
Answer:
k = 6 OR k = -6
Step-by-step explanation:
Given Equation is:
=> [tex]x^2+kx+9=0[/tex]
To Find the value of k, we'll find it's discriminant:
Comparing the above equation with standard form of quadratic equation, we get:
a = 1, b = k and c = 9
=> Discriminant = [tex]b^2-4ac[/tex]
D = [tex](k)^2-4(1)(9)[/tex]
D = [tex]k^2-36[/tex]
Given that Equation has only one solution, So D will be equal to 0
0 = [tex]k^2-36[/tex]
Adding 36 to both sides
[tex]k^2 = 36[/tex]
Taking sqrt on both sides
=> k = ±6
Either,
k = 6 OR k = -6