#### Answer

$-17-17i$

#### Work Step by Step

We multiply the two complex numbers using the FOIL method:
Step 1: $wz$
Step 2: $(3+5i)(-4+i)$
Step 3: $3(-4+i)+5i(-4+i)$
Step 4: $-12+3i-20i+5i^{2}$
Step 5: $-12-17i+5i^{2}$
Since $i^{2}=-1$, we substitute the value of $i^{2}$ in the expression and simplify:
Step 6: $-12-17i+5(-1)$
Step 7: $-12-17i-5$
Step 8: $-17-17i$
The answer is in rectangular form.