9h^2+42h+49
no common factors
trial and error
try first term and last term
all sings are positive since last term and middle terms are possitive
factor leading term and coeficient and try those
9=3*3
49=7*7
(3h+7)(3h+7)
9h^2+21h+21h+49
9h^2+42h+49
true
(3h+7)(3h+7)=(3x+7)^2
answer is (3h+7)^2
answe ris ths second one