To find the area of a rectangle, you multiply the base by the height.
So in this case, the base of the rectangle would be 17cm, and the height would be 22.
17 x 22 = 374cm²
You also need to find the area of the triangle.
The area of a triangle is the base multiplied by the height and then halved.
In this case, the base would be 19cm, and the height would be 22 - 10 = 12 (if you minus 10 from 22, you would find the length of the unknown side of the triangle).
19 x 12 = 228
Half of 228 is 114cm²
Add the area of the triangle with the area of the rectangle to give the area of the whole shape.
374 + 114 = 488cm²