Factorise: 25+70x+49x2
(7x+5)(7x+5)
Given, the expression is 25+70x+49x2.
The given expression can be rewritten as,
49x2+70x+25
Using the identity: (a+b)2=a2+2ab+b2,we get
49x2+70x+25=(7x)2+2(5)(7x)+52
=(7x+5)2
=(7x+5)(7x+5)
∴25+70x+49x2=(7x+5)(7x+5)