#### Answer

$(w-18)(w+3)$

#### Work Step by Step

To factor a trinomial in the form $w^2+bw+c$, we must find two numbers whose product is $c$ and whose sum is $b$. We then insert these two numbers into the blanks of the factors $(w+\_)(w+\_)$.
In the case of $w^2-15w-54$, we are looking for two numbers whose product is $-54$ and whose sum is $-15$. The numbers $-18$ and $3$ meet these criteria because: $$-18\times(3)=-54\;\text{and}\;-18+(3)=-15$$When we insert these numbers into the blanks, we arrive at the factors: $(w-18)(w+3)$.