I am not sure how to do this,
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Answer:
I won't tell you the answer but ill tell you how to do it.
Step-by-step explanation:
First, you have to cut the shape, so make one triangle and one square. Then, subtract the ten to the 14 to get 4 so you know how wide the triangle is. Next you work on only the square...for now. You multiply W*H (width times height) then you get a number(10*9). Next you move on to the triangle, You multiply 4 (the number you got by subtracting 10 from 14) by 3 b*h (base times height). When ever dealing with a triangle always divide your answer by two. Once you have the area of the square and the triangle you add both of those together to get your final answer.