Two triangles have the same areas if
 

  • A two sides in one triangle are equal to two sides in the other
  • B three sides in one triangle are equal to three sides in the other
  • C two angles in the triangle are equal to two angles in the other
  • D three angles in one triangle are equal to three angles in the other
  • E one side and the opposite angle in one triangle are equal to one side and the opposite angle in the other
jamb 1978mathematics

The correct answer is D. three angles in one triangle are equal to three angles in the other

Two triangles have the same areas if one side and the opposite angle in one triangle are equal to one side and the opposite angle in the other.

This is known as the "SAS" (Side-Angle-Side) congruence criterion, and it applies when two triangles share one side and the two angles not included between those sides are equal in both triangles. 

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