SAT Math & Desmos Calculator Guide
Introduction
- Desmos calculator is highly useful for SAT exams.
- Many SAT prep platforms still recommend solving problems manually.
- Desmos is fast and accurate.
Desmos Calculator Overview
- Desmos on SAT is the same as the online version with some limitations (no image upload or sound).
Solving Equations with Desmos
Single Variable Equations
- Traditional method: Rearrange the equation to find the solution.
- Desmos method: Input equation and find where the vertical line meets.
Systems of Equations
- Graph both equations.
- Intersection point(s) represent the solution.
- Convert single variable equation to systems of equations to find solutions easily.
Systems of Inequalities
- Input inequalities into Desmos.
- Look for overlapping shaded regions to find solutions.
- Applied to real-world problems like budgeting for buying fruits (apples and bananas).
Quadratics
- Graph quadratics to find intercepts and vertex with Desmos.
- Consider transformations (e.g., f(x) + 5) directly within Desmos.
Quadratic & Linear Intersection
- One solution often means intersection at the vertex.
- Adjust parameters in Desmos to find precise intersection points.
Special Cases & Warnings
- Infinite vs. no solution: A system with single variable can show no solutions when lines overlap completely.
- For linear systems with no solution, calculate slopes to ensure parallel lines.
Functions, Mean & Median
- Desmos can compute medians and means directly.
- For function tables, Desmos can assist but is not always necessary.
Specific Problem Types
Circles
- Recognize the circle formula for center and radius extraction.
- Use Desmos for finding valid x-values on circle perimeters.
Equivalent Expressions
- Not advisable to use Desmos; know how to factor and solve by hand.
When to Use Desmos
- Single variable equations.
- Systems of equations and inequalities.
- Quadratic intersections and solutions.
- Direct computation of mean and median.
- Finding points on circles.
When Not to Use Desmos
- Systems of linear equations with no solution.
- Complex mean and median problems.
- Simple circle calculations (center/radius).
- Equivalent expressions and general algebra.
Conclusion
- Desmos is a powerful tool for the SAT but should be used wisely.
- Understanding the underlying math concepts is crucial.
- Private tutoring available at learnsatmath.com.
Reminder: Practice using Desmos and solving problems by hand to enhance understanding and performance on the SAT.