Question

The number which should be subtracted from 5a2-3ab+7b2 to make it equal to a2+ab+b2 is

Answer 1

Let the no.be x
As in the question 'from'word is given we will take the given no.first
ATQ=5a2-3ab+7b2-x=a2+ab+b(its not in standard form so-)
5a2+7b2-3ab-x=a2+ab+b2
5a2-a2+7b2-b2-3ab-ab=x
4a2+6b2-4ab=x
Thats the answer
Hope it helps!!!
Thankx

Answer 2

Answer:  $4a^2 - 4 ab + 6b^2$

Step-by-step explanation:

Let x be the number that should be subtracted from 5a²-3ab+7b² to make it equal to a²+ab+b²,

⇒ $( 5a^2-3ab+7b^2 ) - x = a^2+ab+b^2$

⇒ $- x= (a^2+ab+b^2) - ( 5 a^2-3ab+7 b^2 )$

⇒ $x= - (a^2+ab+b^2) + ( 5a^2-3ab+7b^2 )$

⇒  $x= (5 a^2-a^2) + (-3 ab - ab) + (7 b^2 - b^2)$

⇒  $x = 4 a^2 - 4 ab + 6b^2$

Hence, the required number is,

$4 a^2 - 4 ab + 6b^2$