w=500+150h
h=hours so it'll be w=500+150(5) because he works for 5 hours.
First, you multiply the hourly charge. 150*5=750. Now plug that into the equation.
w=500+750.
Next, you add the two together. 500+750=1250.
Therefore, the cost of a wedding that lasts 5 hours is $1,250.