Francis should of added 2x to both sides, that was his error.
Answer:
S2 = (S1+S3)/2
Step-by-step explanation:
The area of a trapezoid is the product of the midline length and the height. The parallel lines have divided the height into three equal pieces, so the midline of the middle piece will be the average of the midline lengths of the top and bottom pieces.
The result is that the area of the middle part is the average of the areas of the top and bottom parts:
S2 = (S1+S3)/2
A triangle not only has inside angles but outside angles as well. When a triangle's side is extended, the extension creates another angle. This angle, called an outside or exterior angle, has a special relationship with the angle adjacent to it. The two angles become supplementary angles, which are angles that have a combined measurement of 180 degrees. You can find the measurements of a triangle's outside angles by working with the measurements of its inside ones.<span>
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