Question

if one of the zeroes of f (x) is x2-kx+10is 2 find the value of k and the other zero

Answer 1

Hi friend!!

Put x = 2 in f(x) as 2 is one of the zeroes of the polynomial.

f(2) = (2)² - k(2) + 10 = 0
4-2k+10 = 0
14-2k = 0
2k = 14
k = 7

f(x) = x²-kx+10 = x² - 7x + 10

Let the other zero be ß

We know that, sum of zeroes = -x coefficient/x² coefficient

2 + ß = -(-7)/1

2 + ß = 7

ß = 7-2
=> ß = 5

Therefore, the other zero is 5

Answer 2

Hi friend!!

f(x) = x² - kx + 10

f(2) = 0
so ,
f(2) = (2)² - k(2) + 10 = 0

4 -2k +10 = 0

14 - 2k = 0

2k = 14

k = 7

now , as we got the value of k ,

f(x) = x² - 7x + 10
a = 1 , b = -7 , c = 10

Let the other zero be "x"

S of zeroes = -b/a

2 + x = -(-7)/1

2 + x = 7

x = 7 - 2

x = 5

Hence , the other zero is 5