Question

Final a numbers whose sum is 15 and product is 20.

Answer 1

Question :

Find a numbers whose sum is 15 and product is 20.

Solution :

• Let first number be M and second number be N.

» Sum of two numbers is 15.

→ M + N = 15

→ M = 15 - N _________ (eq 1)

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» Product of two numbers is 20.

→ MN = 20

→ (15 - N)N = 20 [From (eq 1)]

→ 15N - N² = 20

→ - N² + 15N - 20 = 0

→ N² - 15N + 20 = 0

The above equation can't be solved with quadratic formula and factorization.

So, it is not possible to find the numbers of this equation.

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Answer 2

SOLUTION

Let two numbers are x & y.

A/q,

x+y= 15........(1)

x×y= 20........(2)

From equation (1) to get,

x+ y= 15

=) x= 15-y..........(3)

Putting the value of x in equation (2),

$x \times y = 20 \\ = > (15 - y) \times y = 20 \\ = > 15y - {y}^{2} = 20 \\ = > - {y}^{2} + 15y = 20 \\ = > {y}^{2} - 15y + 20 = 0$

There is not possible to factorisation.

Krishna ❤️