Question

The sum of two numbers is 30 and their difference is 12, what are the two numbers​

Answer 1

$\sf{\bold{\blue{\underline{\underline{Given}}}}}$

•The sum of two numbers is 30.

•difference of that two number is 12.⠀⠀⠀⠀

$\sf{\bold{\red{\underline{\underline{To\:Find}}}}}$

⠀⠀⠀⠀ Find the two numbers?

$\sf{\bold{\purple{\underline{\underline{Solution}}}}}$

Let,

the two numbers are a and b

so,

According to the question,

Sum of two number is 30

$\rightsquigarrow{a+b=30}••••••••••••(<strong>1</strong><strong>)</strong>$

difference of two number is 12

$\rightsquigarrow{a-b=12}••••••••••••••(<strong>2</strong><strong>)</strong>$

Now,

add the equation 1 and equation 2.

we get that,

$\tt{a+b+a-b=30+12   }$      

$\tt{a+\cancel{b}+a-\cancel{b}=42   }$      

$\tt{ 2a=42  }$      

$\tt{ a=\dfrac{42}{2}  }$      

$\therefore{\bold{ a=21  }}$      

So, one number is =a=21.

Now put the value of a in equation 2.

we get that,

$\tt{a-b=12   }$      

$\tt{ 21-b=12  }$      

$\tt{ b=21-12  }$      

$\therefore{bold{ b=9  }}$ 

So,The other number is =b=9.

$\sf{\bold{\green{\underline{\underline{Answer}}}}}$

⠀⠀⠀⠀

$\pink{\mapsto{\pink{So~ the~ two~ numbers~ is~ 21~ and ~9.  } }}$