Math Problem Statement

请帮我解一下这道题

Solution

The problem involves a square ABCDABCD with side length 1, where BE=2ECBE = 2EC and CF=FDCF = FD. The task is to find the area of triangle AEGAEG.

Let's break it down step by step:

  1. Find the coordinates of point EE:

    • Given that BE=2ECBE = 2EC, let EC=xEC = x.
    • Since BE+EC=1BE + EC = 1 (because BC=1BC = 1), we have 2x+x=12x + x = 1, which gives 3x=13x = 1, so x=13x = \frac{1}{3}.
    • Therefore, EC=13EC = \frac{1}{3} and BE=23BE = \frac{2}{3}.
    • Point EE is (0,23)\left(0, \frac{2}{3}\right).
  2. Find the coordinates of point FF:

    • Given that CF=FDCF = FD, let CF=yCF = y.
    • Since CF+FD=1CF + FD = 1 (because CD=1CD = 1), we have y+y=1y + y = 1, which gives 2y=12y = 1, so y=12y = \frac{1}{2}.
    • Therefore, CF=12CF = \frac{1}{2} and FD=12FD = \frac{1}{2}.
    • Point FF is (12,1)\left(\frac{1}{2}, 1\right).
  3. Find the coordinates of point GG:

    • Point GG is the intersection of ADAD and EFEF.
    • Line ADAD is x=0x = 0.
    • Line EFEF has endpoints E(0,23)E(0, \frac{2}{3}) and F(12,1)F(\frac{1}{2}, 1).
    • The equation of line EFEF can be found using the slope formula: m=123120=1312=13×21=23m = \frac{1 - \frac{2}{3}}{\frac{1}{2} - 0} = \frac{\frac{1}{3}}{\frac{1}{2}} = \frac{1}{3} \times \frac{2}{1} = \frac{2}{3}
    • The equation of the line is y=23x+23y = \frac{2}{3}x + \frac{2}{3}.
  4. Find the coordinates of point GG:

    • Since GG lies on ADAD, x=0x = 0.
    • Substitute x=0x = 0 into the equation of EFEF: y=23×0+23=23y = \frac{2}{3} \times 0 + \frac{2}{3} = \frac{2}{3}
    • Therefore, point GG is (0,23)(0, \frac{2}{3}).
  5. Calculate the area of triangle AEGAEG:

    • The coordinates of AA are (0,1)(0, 1).
    • The coordinates of EE are (0,23)(0, \frac{2}{3}).
    • The coordinates of GG are (0,23)(0, \frac{2}{3}).

Since points EE and GG are the same in this case, triangle AEGAEG is degenerate, meaning it has zero area.

Therefore, the area of triangle AEGAEG is 00.

If you have any questions or need further details, please let me know. Here are five more questions you might want to ask:

  1. How do you find the equation of a line given two points?
  2. What is the slope-intercept form of a linear equation?
  3. How can you determine if a triangle is degenerate?
  4. How do you find the area of a triangle given its vertices?
  5. What are some properties of triangles in a square?

Tip: Always verify if the given conditions make the points collinear, as this can simplify solving the problem.

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Math Problem Analysis

Mathematical Concepts

Geometry
Coordinate Geometry
Triangle Properties

Formulas

Slope formula

Theorems

Properties of triangles in a square

Suitable Grade Level

Grades 10-12