Fortunately, secure grounding in particular concepts of linear, quadratic, and exponential functions tested on the SAT isn't hard to attain.
Following are key facts about linear, quadratic, and exponential models students must know to answer SAT interpretation questions.
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Linear functions
y = mx+b: y-intercept b is the “initial value” (y value when x = 0).
Slope is the “rate of change” (y compared to x, “y per x”).
Quadratic functions
y = ax^2+bx+c: y-intercept c is the “initial value” (y value when x = 0).
max/min value is the y coordinate at the vertex.
Exponential functions
y = A*B^x.
x is usually time, t.
A is the initial value (y value when x or t = 0).
B is the “multiplier” (number repeatedly multiplied in the problem.
B = 1 ± r, where r is the rate of increase or decrease (respectively)..
For example: If the rate of decrease is 15%, B = 85% = .85.
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For practice, search Google for “SAT interpretation questions worksheets,” pick a worksheet that provides answers, complete the worksheet, analyze any mistakes, and redo it until you can complete that worksheet with no errors. Then repeat, with additional worksheets, as needed, until you’ve mastered this important subtopic.
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