Question

If − 1 /2 is a zero of the quadratic polynomial x2 +kx - 5 , then the other zero is

Answer 1

Answer:

p(x)=x^2+kx-5=0

p(-1/2)=(-1/2)^2+-1/2k=5

p(-1/2)=1/4-1/2k=5

p(-1/2)=-1/2k=5-1/4

p(-1/2)=-1/2k=19/4

k=-19/2

Therefore k=-19/2

Answer 2

Extension of above answer.
K = -19/2
So
p(x) = x^2 -19/2x- 5

Multiply by 2
2x^2 -19x-10 =0
2x^2 -20x + x -10 = 0
2x ( x-10) +1 ( x-10)= 0

So x = -1/2, 10
Other zero of p(x) = 10