Question

a square minus b square =19,find a?​

Answer 1

Answer:

10

Step-by-step explanation:

A²- B² =19.

Since 19 is a prime number so only possible way to get 19 Is 19.1

So (a+b)(a-b)=19.1

So

a+b = 19 and a-b =1

Solving we get a= 10 and b=9.

Answer 2

The value of a is 10.

Explanation:

Given : $a^2-b^2= 19$

Let a and b are any positive integers.

Using identity :

$a^2-b^2=(a-b)(a+b)$ , we have

$(a+b)(a-b)=19$

Since 19 is a prime number so , we can write is as 19 =  19 x 1 , so our expression becomes.

$(a+b)(a-b)=19\times1$

Since a and b are positive integers , it means

$a+b=19------------(1)\\\\ a-b=1----------(2)$

Add (1) and (2) , we get

$2a=20\Rightarrow\ a=10$

From (2) , $10-b=1\Rightarrow\ b=9$

Hence, the value of a is 10.

# Learn more :

Factorise a minus b minus a square + b square

Report by Sriganeshandco627 28.04.2019

https://brainly.in/question/9559116