00:01
All right, we're given an isosceles trapezoid here, and we're asked to find the exact area.
00:06
So the best way to go about this is almost always to divide and conquer.
00:11
So we can cut this into two triangles and a rectangle.
00:16
And so, with the two triangles, if this is, if this top piece here is 20, then this bottom piece down here, cutting out those two triangles here is also 20.
00:28
So we can extrapolate that this would have to be five and this would have to be five to make up for the missing 10 from the 30.
00:36
And so now for both triangles, we have the same angle, sides, and so we can use the area formula for the triangle.
00:45
One half, ab, sign of 60 in this case.
00:51
And so a, b, so that's 10 times 5, divided by two.
00:56
So area is equal to 1 1 half 10 times 5.
01:02
And then the sign of 60 is root 3 over 2.
01:07
And so i can cancel off this into 5...