The formula for finding the area of a regular polygon is 1/2(apothem)(perimeter).
Well, since this is a nonagon (9 sides) and each side has a length of 7, so 7 times 9 equals 63 (perimeter of the shape).
Now, we have all the information we need to plug into our formula:
1/2(5)(63). I already set up the equation for you, so you just need to evaluate it.