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Solving an equation involving fractions. 315 x 2 x 315 2x x 2 x Variable in denominator 6 x 10 6 6 x 4 Restriction: x 0 Since our answer is not 0 we are ok We are going to multiply through by the LCD to get rid of the fractions LCD 2x We multiply the top by what isn’t in the bottom – the bottoms cancel out We have to be careful that x doesn’t make the denominator 0 Solve. 2 x 2 1 x 2 x 2x 2 x 1 Restriction: x 2 x 2 x(x 2) or x 0 2 x x(x 2) 1 LCD x(x+2) x 2 x(x 2) 2x x x(x 2) 2 x x 2x x x 2 0x x 0 x(x 1) x 0 or x 1 Objective - To use proportions to solve problems. Proportion - A statement of equality between two ratios. a c b d extremes Solve for x. 1) 3 x 5 20 60 5x 5 5 12 x means ad bc 2) 5 30 7 x 5x 210 5 5 x 42 Solve the proportions below. 2x 5 1) 3 30 60x 15 60 60 1 x 4 2x 1 5 2) 4 3 3(2x 1) 20 6x 3 20 3 3 6x 17 6 6 17 5 x or 2 6 6