Question

x²-(k+1)x+9=0 find the value of k if they have equal real roots​

Answer 1

Answer:

x² -(k+1)x + 9=0 Equation have equal real roots

i.e., b²-4ac = 0

b = -(k+1), a = 1, c = 9

[-(k+1)]² - 4×1×9 =0

=> k² + 1 + 2k - 36 =0

=> k² + 2k - 35 =0

=> k² + 7k - 5k - 35 =0

=> k(k + 7) -5(k + 7) =0

=> (k + 7) (k - 5) =0

i.e., k = -7 or k = 5.