Question

find the quadratic polynomial whose one zero is 5 & the product is 30....

Answer 1

Let the zeros is the polynomial be m and n

According to the question ;
m = 5
mn = 30

n = 30/5
n = 6

The required polynomial with zeros m and n is;

x²-(m+n)x+(mn) = 0

x²- (5+6)x + (5.6) = 0

x² - 11x + 30 = 0
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Answer 2

let the zeroes be x and y

 x = 5
xy = 30

y = 30/5
y = 6

apply the formula
p(x)= x²- (sum of the zeroes)+ ( product of zeroes)
      = x²-x(5+6) + (5×6)
      = x²- 11x + 30

reqired polynomial is x²- 11x + 30..

hope it helps..