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A polynomial is an expression like 2x^3 - 5x + 1. The degree is the highest exponent. The factor theorem says (x - a) is a factor of P(x) if and only if P(a) = 0. Use this to factor cubic polynomials.

Quadratic equations have the form ax^2 + bx + c = 0. The quadratic formula is x = (-b +/- sqrt(b^2 - 4ac)) / (2a). The discriminant b^2 - 4ac tells whether there are 2, 1, or 0 real roots.

In a right triangle, sin(theta) = opposite/hypotenuse, cos(theta) = adjacent/hypotenuse, tan(theta) = opposite/adjacent. Use SOH-CAH-TOA. Many Ethiopian geography problems (e.g. height of Mt. Ras Dashen using angle of elevation) use trigonometry.

Given two points (x1, y1) and (x2, y2): distance = sqrt((x2-x1)^2 + (y2-y1)^2), slope = (y2-y1)/(x2-x1). The equation of a line is y = mx + c.