Question

. Factorise: 169y2 - 4x²​

Answer 1

$\sf 169y^2-4x^2 \\\\\sf =(13y)^2-(2x)^2 \\\\\sf </p><p>=(13y+2x)(13y-2x) \\\\\sf \because a^2-b^2=(a+b)(a-b)</p><p>$