Count the number of Little boxes there are on each side Like I did in the picture below. Then separate the triangle and the rectangle so that you can find the area of the rectangle first which you can figure out with just doing base times height. Then find the area of the triangle which is base times height divided by 2. The area of the rectangle should be 20 and the area of the triangle should be 6. Then you just add the two together so the area of a trapezoid should be 26. Now this is the area of the trapezoid not the perimeter. Perimeter and area are different things to find the perimeter you just count the outside lines of the trapezoid so it would be 5+4+5+3 Plus the long side of the triangle which you find by using Pythagorean theorem (A squared plus B squared equals C squared) I also show this in the picture below.
There exists a trigonometric identity which states that, sin (A - B) = sin A cos B - cos A sin B This is very similar to the given expression with A equal to 57° and B equal to 13°. The simplified form of the angle is, sin (57° - 13°) = sin 44°
