Using the defects method, which relationship represents the Law of Cosines if the measure of the included angle between the sides a and b of ΔABC is less than 90°?

area of square c2 = -area of square a2 − area of square b2 + area of defect1 + area of defect2

area of square c2 = area of square a2 + area of square b2 + area of defect1 − area of defect2

area of square c2 = area of square a2 + area of square b2 − area of defect1 − area of defect2

area of square c2 = area of square a2 + area of square b2 + area of defect1 + area of defect2

Question

Using the defects method, which relationship represents the Law of Cosines if the measure of the included angle between the sides a and b of ΔABC is less than 90°?

area of square c2 = -area of square a2  − area of square b2 + area of defect1 + area of defect2

area of square c2 = area of square a2  + area of square b2 + area of defect1 − area of defect2

area of square c2 = area of square a2  + area of square b2 − area of defect1 − area of defect2

area of square c2 = area of square a2  + area of square b2 + area of defect1 + area of defect2