What’s the answer ?

Answer:
285 cm²
Step-by-step explanation:
You can divide the figure into a square and a triangle and figure the areas of each. Then the total area is the sum of those.
... for the square: A = s² = (15 cm)² = 225 cm²
... for the triangle: A = (1/2)bh = (1/2)(8 cm)(15 cm) = 60 cm²
Then the total area is ...
... A = square area + triangle area = (225 +60) cm² = 285 cm²
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If you like, you can consider the figure to be a trapezoid, with bases of length 15+8 = 23 cm (lower) and 15 cm (upper). Its height is 15 cm.
The area of a trapezoid is given by ...
... A = (1/2)(b1 +b2)h = (1/2)(23 cm +15 cm)(15 cm) = (19 cm)(15 cm) = 285 cm²