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The diagram shows a trapezium ABCD in which BC is parallel to AD and angle BCD=90.the coordinates of A,B,C,D are (2,0)(4,6)(12,5)respectively.

Find(i) find the quations of BC and CD

User Purushoth
by
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2 Answers

1 vote

Answer:

BC: x + 8y = 52

CD: x - 8y = 2

Explanation:

This is correct

User TWilly
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4 votes

The equations are BC: x + 8y = 52 and CD: x - 2y = -2, derived using point-slope form with slopes calculated from the given coordinates of the trapezium.

To find the equations of the lines BC and CD, we can use the point-slope form of the equation, which is given by "y - y₁ = m(x - x₁)," where (x₁, y₁) is a point on the line, and m is the slope.

1. **Equation of BC:**

The slope of BC is given by the difference in y-coordinates over the difference in x-coordinates. So,

The slope of BC (m₃) = (5 - 6) / (12 - 4) = -1 / 8.

Now, using the point-slope form with point B (x_B, y_B) = (4, 6),

y - 6 = (-1/8)(x - 4)

Simplifying,

8(y - 6) = -1(x - 4)

8y - 48 = -x + 4

x + 8y = 52

So, the equation of BC is x + 8y = 52.

2. **Equation of CD:**

Since BC is parallel to AD, CD must also have the same slope. The slope of AD is

The slope of AD (m₂) = (0 - 5) / (2 - 12) = 5 / 10 = 1 / 2.

So, using the point-slope form with point D (x_D, y_D) = (12, 5),

y - 5 = (1/2)(x - 12)

Simplifying,

2(y - 5) = 1(x - 12)

2y - 10 = x - 12

x - 2y = -2

Thus, the equation of CD is x - 2y = -2.

User Matt Jewett
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