You can put this solution on YOUR website! to solve this, multiply the coefficent of h^2 by 36.that is
1*36
then look for two nos such that when u multiply them it gives u 36 an when you add them gives you -13 that is to say
-4&-9
now replace 13h with these nos,it will give you
{(h^2)-(4h)-(9h)+36}=0
then factorize
h(h-4) 9(-h+4)=0
now multiply the first by 1 and the second by -1
h(h-4)-9(h-4)=0
(h-4)(h-9)=0
h=4 or 9
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