well first you should work on the rectangle so since that is l x w
You would do 12*18 which would be 216
so now you got the area of the rectangle now since we know the base and height of the triangle you would do 7*18*1/2 which would be 28
so now you add 216 and 28 which would be 244 which would be your answer
hope this helps
P.S the base of the triangle is the width of the rectangle in this problem