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In the proof of the triangle angle sum theorem, you must draw an auxiliary line. which construction must you use to draw this line?

Find the product of (4x + 3y)(4x − 3y). 16x2 − 24xy + 9y2 16x2 − 9y2 16x2 + 24xy + 9y2 16x2 + 9y2

Which approach to the theory-and-research cycle does the following sequence reflect: (1) specific observations suggest generalizations, (2) generalizations produce a tentative theory, (3) the theory is tested through the formation of hypotheses, and (4) hypotheses may provide suggestions for additional observations?