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  • Chemistry – Chemical Equations

    Chemical Equations

    Welcome! In this lesson, we will learn about chemical equations.

    Start

    Summary

    Chemical Equation:

    A way to show a chemical reaction using formulas

    Coefficients:

    Numbers in front of formulas show how many molecules participate

    Arrow (→):

    Shows the direction of the reaction

    Examples:

    2H₂ + O₂ → 2H₂O

    2Mg + O₂ → 2MgO

  • Chemistry – Chemical Reactions

    Chemical Reactions

    Welcome! In this lesson, we will learn about chemical reactions.

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    Summary

    Chemical Reaction:

    A process where substances change into new substances

    Reactants:

    Substances before a reaction

    Products:

    Substances after a reaction

    Energy:

    Some reactions release energy

    Some reactions need energy

  • Chemistry – Chemical Formulas

    Chemical Formulas

    Welcome! In this lesson, we will learn about chemical formulas.

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    Summary

    Chemical Formulas

    Subscripts (numbers):

    H₂O → 2 hydrogen atoms, 1 oxygen atom

    CO₂ → 1 carbon atom, 2 oxygen atoms

    Ionic Compounds:

    Na⁺ + Cl⁻ → NaCl

    Mg²⁺ + Cl⁻ → MgCl₂

  • Math – Quadratic Functions3

    Quadratic Functions3

    Welcome! In this lesson, we will study how to find the intersection of 2 functions.

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    Summary

    Intersection of Quadratic Functions: Points where two quadratic functions have the same y-value

    Method: Set the two functions equal → form a quadratic equation → solve for x → substitute x into either function to get y

    Tips: 2 solutions → 2 intersection points, 1 solution → graphs touch at 1 point, 0 solutions → no intersection

  • Math – Quadratic Functions2

    Quadratic Functions2

    Welcome! In this lesson, we will learn how to find minimum or maximum of a quadratic function.

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    Summary

    Quadratic Function: y = ax² + bx + c

    Vertex: Found by completing the square

    Minimum value of y: the y-coordinate of the vertex when a > 0

    Maximum value of y: the y-coordinate of the vertex when a < 0

  • Math – Quadratic Functions1

    Quadratic Functions

    Welcome! In this lesson, we will learn about quadratic functions.

    Start

    Summary

    Quadratic Function: y = ax² + bx + c

    Graph: Parabola (U-shaped curve)

    Vertex: Found by completing the square

    Example 1: y = x² + 4x + 1 → complete square: (x + 2)² – 3 → vertex: (-2,-3)

    Example 2: y = 2x² – 4x + 3 → complete square: 2(x – 1)² + 1 → vertex: (1,1)

  • Math – Completing the Square

    Completing the Square

    Welcome! In this lesson, we will learn about completing the square.

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    Summary

    Completing the Square

    Purpose:

    Rewrite a quadratic expression into a square form.

    Example 1:

    x² + 4x + 1

    x² + 4x + 4 − 4 + 1

    = (x + 2)² − 3

    Example 2:

    2x² − 4x + 3

    2(x² − 2x) + 3

    2((x − 1)² − 1) + 3

    = 2(x − 1)² + 1<

  • Math – Linear Functions2

    The intersection of two lines

    Welcome! In this lesson, we will learn how to find the intersection of two lines.

    Start

    Summary

    Intersection of two lines: Point where two lines meet

    Step 1: Set the two functions equal

    Step 2: Solve for x

    Step 3: Substitute x to find y

    Example: y = 2x + 1, y = -x + 4 → Intersection = (1, 3)

  • Math – Linear Functions1

    Linear Functions

    Welcome! In this lesson, we will study linear functions.

    Start

    Summary

    Linear Function: A function that makes a straight line

    Form: y = ax + b

    Slope (a): How much y changes when x increases by 1

    y-intercept (b): The value of y when x = 0

    Example: y = 2x + 1 → a = 2, b = 1

  • Math – Spheres

    Spheres

    Welcome! In this lesson, we will learn about spheres.

    Start

    Summary

    Sphere: A perfectly round three-dimensional object, like a ball

    Radius (r): Distance from the center to the surface

    Volume (V): V = 4/3 × π × r³

    Surface area (S): S = 4 × π × r²