How did the answer be area =90 in. square

90 in^2

Step-by-step explanation:

Break the diagram in two shapes i.e. rectangle and triangle.

The rectangle sides are 10 inch and 8 inch.

The are of Rectangle can be found by the formula

Area of Rectangle = length(L) * Breadth(B)

Area of Rectangle = 10*8

Area of Rectangle = 80 in^2

Now for triangle,

Total Base = 13, Breadth of rectangle is 8 inch so the base of triangle = 13 - 8 = 5

The height of triangle = 10 - 6 = 4 inch  

The formula of area is:

Area Of triangle = (Height * Base)/2

Area of Triangle = (4 * 5)/2

Area of Triangle = 20/2

Area of Triangle = 10 in^2

Total area of the shape = Area of rectangle + Area of triangle

Total area of the shape = 80 + 10

Total area of the shape = 90 in^2

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