factorise:7m^2+67m+36
You know the first terms of the factors must be 7 & 1, since those are the only factors of 7.So you write: \((7m+x)(m+y)\)Both the second and third term are positive, so x & y are both positive. From there, all you can really do is plug in all factors of 36 as x or y until you find that the second term adds up to 67.And you find the only one that works is:\((7m+4)(m+9)\)