Answer :
[tex]k^{2}-8k-20=0 \\ (k-10)(k+2)=0 \\ \\ k-10=0 \\ k=10 \\ \\ k+2=0 \\ k=-2 \\ \\ \boxed{k=-2\ and\ 10}[/tex]
k² - 8k - 20 = 0
k = -(-8) +/- √((-8)² - 4(1)(-20))
2(1)
k = 8 +/- √(64 + 80)
2
k = 8 +/- √(144)
2
k = 8 +/- 12
2
k = 8 + 12 k = 8 - 12
2 2
h = 20 k = -4
2 2
x = 10 k = -2
k = -(-8) +/- √((-8)² - 4(1)(-20))
2(1)
k = 8 +/- √(64 + 80)
2
k = 8 +/- √(144)
2
k = 8 +/- 12
2
k = 8 + 12 k = 8 - 12
2 2
h = 20 k = -4
2 2
x = 10 k = -2
