Question

The sum of two numbers is 20. Find the numbers if their product is 91 . Please the answer was According to Class- 6 ​

Answer 1

Divide 20 by 91 and that's you got the answer.

Step-by-step explanation:

20÷91

Answer 2

$\large\underline{\sf{Solution-}}$

Given that

☆ Sum of two numbers is 20

So, Let we assume that

☆ First number is x

and

☆ Second number is 20 - x

According to statement,

☆ Product of two numbers = 91

$\rm :\longmapsto\:x(20 - x) = 91$

$\rm :\longmapsto\:20x - {x}^{2} = 91$

$\rm :\longmapsto\: {x}^{2} - 20x + 91 = 0$

Now we have to split the middle terms to factorize this quadratic equation.

We have to split 91 in such a way that on adding we get ( - 20 ) and on multiply we get 91. So such pair is ( - 13 ) and ( - 7 ).

So, splitting of middle terms is represented as

$\rm :\longmapsto\: {x}^{2} - 13x - 7x + 91 = 0$

$\rm :\longmapsto\:x(x - 13) - 7(x - 13) = 0$

$\rm :\longmapsto\:(x - 13)(x - 7) = 0$

$\rm :\longmapsto\:x - 13 = 0 \: \: or \: \: x - 7 = 0$

$\bf\implies \:x = 13 \: \: or \: \: x = 7$

When x = 13, so Second number = 20 - 13 = 7

and

When x = 7, so Second number = 20 - 7 = 13

Hence,

• Two numbers are 13 and 7.