Sat Math Concepts

Function Equations -- f(x)= cx^2 + 30 and f(3)=12 What is value of f(-3)? When you get a function equation, take the other given equation and plug it into the function equation and solve for the variable that was not given. After solving the variable, plug in back into the original equation and then use the the given f(x) of the equation. Remember f(x) just means the given value of x. Correct Answer: 12 Fractional Exponents -- If a-4b=18, what is the value of 3^a/81^b To divide numbers with exponent, the bases must be the same. So convert the numbers to have the same base. Then when raising a number with an exponent to an exponent multiply the exponents. After since they're the same base, you are able to subtract their exponents. Correct Answer: 3^18 Simplifying Complex Fractions -- 1 divided by 1/y-4 + 1/y-3 Simplify the fraction by plugging in a number. Then add the fractions in the denominator by using the bowtie method. Then when dividing a fraction flip the bottom fraction and multiply. Then plug in number to answer choices, and find the one that equal the simplified fraction. Correct Answer: y^2-7y+12/2y-7 Bowtie Method Look at image. Parallel Lines = Same Slope + Slope Formula *PR, p.130, #5 y2 - y1/x2 - x1 Simplified and factored high exponential equations Use bitesized pieces and process of elimination. Bitesized pieces means to take only the first term and evaluate how each one of the answers would be expanded and if it equals the original first term in the unsimplified equation. Point Slope Formula y-y1=m(x-x1) where m is the slope and (x1,y1) is a point on the line Slope Intercept Formula y=mx+b (Slope is M and y intercept is B) Complex Exponents -- (k^(x^(2 + xy) (k^(y^(2 + xy) = k^25