The discussion focuses on determining the values of k for which the quadratic equation x² - kx + 4 = 0 has equal roots by using the discriminant method. The discriminant is calculated as k² - 16, derived from substituting a = 1, b = -k, and c = 4 into the formula b² - 4ac. For the roots to be equal, the discriminant must equal zero, leading to the equation k² - 16 = 0. The solutions for k are k = 4 and k = -4, indicating these are the values that yield equal roots.
PREREQUISITESStudents studying algebra, particularly those learning about quadratic equations and their properties, as well as educators looking for examples of using the discriminant to find conditions for equal roots.
Which means b is NOT "-1", it is "-k". (That's the whole point of algebra isn't it- that numbers are represented by letters?) The discriminant is, as you say b^2- 4ac which, here, is (-k)^2- 4(1)(4)= k^2- 16[/math].<br /> <br /> Now, in order to have equal roots, what must be true of the discriminant? What values of k make that true?priscilla98 said:Homework Statement
Use the disciminant to determine all values of k that would result in the equation x^2 - kx + 4 = 0 having equal roots.
Homework Equations
x = -b +/- (square root) b^2 - 4ac and divide by 2a
or b^2 - 4ac
The Attempt at a Solution
a = 1
b = - 1
c = 4
I'm a little confused with this problem because instead of a number by b there's a k.