Help please! Does mapping the triangle DEF onto triangle GHI prove the two triangles are congruent? Explain your reasoning.

Yes, and there are actually several methods to do so. One method to ensure congruency is to rotate and translate the triangle onto the other, which does not change the shape or size, only where it is. They perfectly match each other when rotated and translated, showing perfect congruency. Another way to ensure congruency is to find angle lengths/slope. Using the slope formula (rise/run), we can find both slopes (whch is the distance in this case) of each side length of both triangles. The angle lengths and slopes are equal to each other.

10 * 563.67 = 5636.7

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