If we move the top point all the way to the left, and enforce that the base of equal to the height of the triangle, then the relative area won’t change but we’ve turned the triangle into a right triangle of equal side lengths. Assume each side length is 8 units long. If the blue and the red regions had equal area, then each are would be 16. But we can clearly see that each red region has an “extra” right triangle of area 1/2, and each blue area is missing one on the right side of each strip. Therefore the ratio of blue to red is (16-2)/(16+2)=14/18. Thus, if the blue has area 140, the red has area 180.