1. Fractional Equations Solving Fractional Equations Unknown Variables in More Than One Term Common Electronics Equations Roots of Quadratic Equations Quadratic Formula

2. Solving Fractional Equations Rule 9 ‑ 1: To solve an equation that includes fractions or mixed numbers: 1. get rid of the fraction (or mixed number); 2. solve for the unknown; 3. verify your answer. 1/3 + a/4 = 2 12(1/3 + a/4) = 212 4 + 3a = 24 3a = 20 a = 20/3 = 6 2/3

3. Unknown Variables in More Than One Term Key Point: When unknown variables appear in more than one term, we must factor out the unknown to arrive at a solution. ER, = V 1 R 1 + V 2 R 2 Solve for R 1. ER 1 ‑ V I R 1 = V 2 R 2 R 1 (E ‑ V 1 ) = V 2 R 2 R 1 = V 2 R 2 / (E ‑ V 1 )

4. Common Electronics Equations The value of total resistance of two resistors in parallel. The voltage gain of a non ‑ inverting op ‑ amp amplifier.

5. Roots of Quadratic Equations Key Point: Quadratic equations are second ‑ degree equations and have two solutions or roots x 2 + 7x + 12 = 0 (x + 3)(x + 4) = 0 x + 3 = 0 x = -3 x + 4 = 0 x = -4

6. Quadratic Formula You can apply the quadratic formula to a quadratic equation in the form ax 2 + bx + c = 0