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tdeaguero1989
what multiple of L of equation 1 should be subtracted from equation 2? ax+by=f cx+dy=g. the first pivot is a(assumed nonzero). Elimination produces what formula for the second pivot?What is y? The second pivot is missing when ad = bc.
Multiple would be c/a .. by subtracting 2 by eqn1 *c/a you eliminate x and solve for y. Yes the second pivot would disappear if ad = bc. Why?? you can solve mathematically but you can also think geometrically. ad = bc means both lines are parallel and hence no solution is possible.