Geometry Question

The area of the larger square is  9 square units

Note that we also have four other triangles bordering the smaller triangle each with an area of

(1/2) * 1 * 2  =   1 square unit....so 4 of them have an area of 4 square units

So....the area of the smaller triangle is   [ 9 - 4]  =  5 square units

So....the area of the smaller triangle is 5/9 that of the larger triangle

Find the areas of the triangles around it (which is 4 units) and subtract it from the entire square (9 units)

OR

Find the areas of each traingle inside the square and add 1 unit for the square by itself in the middle