How to use Desmos graphing calculator on Digital SAT

SAT Quantum
7 Feb 202306:36

TLDRThis video tutorial demonstrates how to use Desmos graphing calculator for solving various types of questions on the new digital SAT. It covers five examples, including solving quadratic equations, utilizing the quadratic formula, graphing circles to find radius and center, and dealing with linear equations and systems. The video highlights the ease of solving these problems with Desmos, showcasing its power as a tool for simplifying complex math questions.

Takeaways

  • 📊 Desmos graphing calculator can be used to solve various types of questions on the new digital SAT.
  • 🔢 Quadratic equations can be solved by graphing them on Desmos to find the larger of two solutions.
  • 🔍 Zooming in and out on the graph is necessary to accurately identify solutions and other graph features.
  • 📐 Quadratic equations with solutions involving radicals can be identified by graphing and comparing with answer choices.
  • ⭕ Circles' equations can be graphed to find the radius or the coordinates of the center by locating the endpoints of the diameter.
  • 🔄 For linear equations with absolute values, graphing on Desmos can help find the exact solution.
  • 🤝 Systems of linear equations can be solved by graphing both equations to find the point of intersection.
  • 🔎 Desmos calculator can simplify solving equations without needing to manually apply formulas like the quadratic formula.
  • 🤔 The effectiveness of using Desmos on the SAT will depend on the types of questions asked in the actual exams.
  • 💡 Desmos is a powerful tool that can help students approach a variety of mathematical questions more efficiently.

Q & A

  • What is the main purpose of the video?

    -The main purpose of the video is to demonstrate how to use the Desmos graphing calculator to solve various types of math questions on the new digital SAT.

  • What is the first type of question discussed in the video?

    -The first type of question discussed is solving quadratic equations, specifically finding the larger of two solutions to a given quadratic equation.

  • How does the Desmos calculator help in solving quadratic equations?

    -The Desmos calculator helps by allowing users to graph the quadratic equation and visually identify the solutions, which can then be compared to find the larger value.

  • What is an example of a quadratic equation provided in the video?

    -An example of a quadratic equation provided is 3(x - 50)^2 = 27.

  • How does the video suggest verifying the solution to a quadratic equation?

    -The video suggests plugging the identified solution back into the original equation to verify if it satisfies the equation.

  • What is the second type of question discussed in the video?

    -The second type of question is related to quadratic equations that may require the use of the quadratic formula or involve radical solutions.

  • How can Desmos help with quadratic equations that have radical solutions?

    -Desmos can help by graphing the equation and allowing users to approximate the solutions, which can then be compared to the answer choices provided.

  • What is an example of a circle-related question that can be solved using Desmos?

    -An example is finding the radius or the coordinates of the center of a circle given its expanded form equation.

  • How does Desmos assist in determining the radius of a circle from its equation?

    -Desmos assists by graphing the circle and allowing users to find the endpoints of the diameter, from which the radius can be calculated as half the diameter's length.

  • What is an example of a linear equation question discussed in the video?

    -An example is solving a linear equation with an absolute value component, such as 3x + |x - 4| = 20.

  • How can Desmos be used to solve a system of linear equations?

    -Desmos can be used to graph both equations simultaneously to find the point of intersection, which represents the solution to the system.

  • What is the potential limitation of using Desmos for SAT questions as discussed in the video?

    -The potential limitation is that if all questions can be easily solved using the calculator, it may not effectively differentiate between students' abilities.

Outlines

00:00

📊 Solving Quadratic Equations with Desmos

This paragraph introduces the use of Desmos calculator for solving quadratic equations, which is particularly useful for the new digital SAT. The speaker provides an example of a quadratic equation (3x - 50)^2 = 27 and demonstrates how to graph it on Desmos to find the larger of the two solutions, which is 53. The paragraph also touches on the possibility of encountering quadratic equations with solutions involving radicals, where the Desmos calculator can help identify the correct answer from a set of options.

05:03

🔍 Exploring Circles and Linear Equations on Desmos

The second paragraph expands on using Desmos for different types of equations, including circles and linear equations. The speaker explains how to graph a circle given by an equation in expanded form and find its radius or center coordinates. An example is provided where the circle's equation is x^2 + y^2 - 2x + 6y + 1 = 0, and the Desmos calculator is used to determine the radius and center. Additionally, the paragraph covers linear equations, including those with absolute values, and how Desmos can be used to find solutions. The speaker also discusses systems of linear equations and the importance of zooming in or out to find the intersection point, which is the solution to the system.

Mindmap

Keywords

💡Desmos graphing calculator

The Desmos graphing calculator is an online tool that allows users to plot mathematical functions and equations. In the context of the video, it is used to solve various types of mathematical problems that are part of the new digital SAT. The video demonstrates how to input equations into Desmos to find solutions, such as the roots of a quadratic equation or the center and radius of a circle.

💡Digital SAT

The Digital SAT refers to the updated version of the Scholastic Assessment Test (SAT) which is now administered digitally. The video is focused on how the Desmos graphing calculator can be utilized as a tool to assist with solving problems on this new format of the SAT.

💡Quadratic equations

Quadratic equations are polynomial equations of the second degree, typically presented in the form ax^2 + bx + c = 0. In the video, the speaker uses Desmos to solve a quadratic equation and find the larger of the two solutions, demonstrating the practical application of graphing calculators in solving such equations.

💡Quadratic formula

The quadratic formula is a method used to find the solutions of a quadratic equation. It is expressed as x = [-b ± sqrt(b^2 - 4ac)] / (2a). The video mentions that while Desmos can be used to find solutions, the quadratic formula is a traditional method that may be necessary for certain types of problems.

💡Zoom in/out

Zooming in and out on the graph is a feature of the Desmos calculator that allows users to adjust the scale of the graph for a closer look or a broader view. The video script refers to this action when finding the exact solutions on the graph of a quadratic equation.

💡Circle equations

A circle equation in the expanded form is given as (x - h)^2 + (y - k)^2 = r^2, where (h, k) is the center of the circle and r is the radius. The video explains how to use Desmos to graph a circle and find its radius or center by identifying the endpoints of the diameter.

💡Linear equations

Linear equations are equations that represent a straight line and are typically in the form y = mx + b, where m is the slope and b is the y-intercept. The video gives an example of a linear equation with an absolute value, showing how Desmos can be used to find the solution.

💡Absolute value

The absolute value of a number is the non-negative value of that number without regard to its sign. In the context of the video, an equation with an absolute value is used to demonstrate how Desmos can graph such equations and find the solution.

💡System of linear equations

A system of linear equations consists of two or more linear equations that are solved simultaneously. The video shows how to use Desmos to graph a system of equations and find the point of intersection, which is the solution to the system.

💡Ordered pair

An ordered pair in the context of the video refers to the solution to a system of equations, where the first number is the x-coordinate and the second number is the y-coordinate. The video explains how to find this ordered pair using Desmos by identifying the intersection point of two graphs.

Highlights

Desmos graphing calculator can simplify solving questions on the new digital SAT.

Five examples are provided to illustrate how to use Desmos for different types of questions.

Quadratic equations can be solved by graphing and identifying the larger solution.

For quadratic equations with radical solutions, Desmos can help identify the correct answer choice.

Desmos is useful for finding the radius or center of a circle given its equation.

Linear equations, even with absolute values, can be solved using Desmos by graphing.

Desmos can find the solution to a system of linear equations by identifying the point of intersection.

The video provides practical examples of how Desmos can be used in the context of the SAT.

Desmos can be used to solve quadratic equations without directly using the quadratic formula.

For circle equations, Desmos can determine the radius and center coordinates.

Desmos simplifies the process of solving linear equations with absolute values.

The video demonstrates how to use Desmos for system of equations questions on the SAT.

Desmos can help students save time on the SAT by quickly solving graph-based questions.

The video suggests that Desmos may make certain SAT questions easier, potentially impacting the differentiation of student abilities.

The effectiveness of Desmos in SAT exams will depend on how questions are designed by the College Board.

Desmos is highlighted as a powerful tool for solving a variety of mathematical questions on the digital SAT.