Scaling A Trapezoid By 1/4 Impact On Dimensions And Area

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When dealing with geometric shapes, scaling plays a crucial role in understanding how dimensions and areas change. In this article, we will explore the effects of scaling a trapezoid by a factor of $ rac{1}{4}$. We'll delve into how the height and area of the trapezoid are affected by this scaling, providing a comprehensive understanding of the underlying principles. Let's consider a trapezoid with specific dimensions and analyze the true statements regarding its scaled version.

Understanding Trapezoids and Scaling

Before diving into the specifics of scaling, it's essential to understand the fundamental properties of a trapezoid. A trapezoid is a quadrilateral with at least one pair of parallel sides. These parallel sides are called the bases, and the non-parallel sides are known as the legs. The perpendicular distance between the bases is the height of the trapezoid. The area of a trapezoid can be calculated using the formula:

Area=12(b1+b2)hArea = \frac{1}{2} (b_1 + b_2)h

where b1b_1 and b2b_2 are the lengths of the bases, and hh is the height.

Scaling a geometric shape involves changing its dimensions proportionally. When a shape is scaled by a factor, all its linear dimensions (such as lengths, widths, and heights) are multiplied by that factor. This process affects not only the size of the shape but also its area and volume (in three-dimensional shapes).

When we scale a trapezoid, we multiply each of its linear dimensions by the scaling factor. This means that the lengths of the bases and the height will all be multiplied by the same factor. As a result, the new trapezoid will be similar to the original trapezoid, but with different dimensions. Understanding these basics is crucial for correctly analyzing how scaling affects the trapezoid's height and area, as discussed in detail later in this article.

Analyzing the Impact on Height

Let's consider the first aspect of scaling: the height of the trapezoid. If a trapezoid is scaled by a factor of $ rac{1}{4}$, its original height will be multiplied by this factor to obtain the new height. Suppose the original height of the trapezoid is 4 feet. When we scale the trapezoid by $ rac{1}{4}$, the new height will be:

NewHeight=OriginalHeight×ScalingFactorNew Height = Original Height \times Scaling Factor

NewHeight=4 ft×14=1 ftNew Height = 4 \text{ ft} \times \frac{1}{4} = 1 \text{ ft}

Therefore, the new height of the trapezoid will be 1 foot. This makes statement A, "The height of the new trapezoid will be 1 ft," a true statement. Statement B, “The height of the new trapezoid will be 16 ft,” is incorrect because it does not reflect the application of the scaling factor. Scaling by $ rac{1}{4}$ implies reducing the dimensions, not increasing them. Thus, understanding the direct impact of the scaling factor on linear dimensions like height is vital for accurate calculations and interpretations.

To further elaborate, it's essential to recognize that scaling linearly affects all one-dimensional measurements. If the initial height were a different value, such as 8 feet, the new height after scaling by $ rac{1}{4}$ would be:

NewHeight=8 ft×14=2 ftNew Height = 8 \text{ ft} \times \frac{1}{4} = 2 \text{ ft}

This illustrates the direct proportionality between the original height and the scaled height. The scaling factor acts as a constant multiplier, reducing the height proportionally. This principle applies uniformly to any initial height, ensuring that the new height is always $ rac{1}{4}$ of the original. This consistency is a fundamental aspect of scaling, maintaining the shape's proportions while altering its size.

In contrast, if we were scaling by a factor greater than 1, such as 4, the height would increase. For example, if the original height was 4 feet and we scaled by a factor of 4, the new height would be 16 feet. However, in this scenario, the scaling factor is a fraction less than 1, indicating a reduction in size. This distinction is crucial in accurately predicting the effect of scaling on different dimensions of the trapezoid.

Examining the Impact on Area

Now, let's consider how scaling affects the area of the trapezoid. The area of a trapezoid is calculated using the formula:

Area=12(b1+b2)hArea = \frac{1}{2} (b_1 + b_2)h

When the trapezoid is scaled by a factor of $ rac{1}{4}$, both the bases (b1b_1 and b2b_2) and the height (hh) are multiplied by this factor. Let's denote the original bases as b1b_1 and b2b_2, and the original height as hh. The new bases will be $ rac{1}{4}b_1$ and $ rac{1}{4}b_2$, and the new height will be $ rac{1}{4}h$. The new area (AnewA_{new}) can be calculated as:

Anew=12(14b1+14b2)(14h)A_{new} = \frac{1}{2} (\frac{1}{4}b_1 + \frac{1}{4}b_2)(\frac{1}{4}h)

Anew=12×14(b1+b2)×14hA_{new} = \frac{1}{2} \times \frac{1}{4}(b_1 + b_2) \times \frac{1}{4}h

Anew=116×12(b1+b2)hA_{new} = \frac{1}{16} \times \frac{1}{2} (b_1 + b_2)h

Since the original area (AoriginalA_{original}) is $ rac{1}{2} (b_1 + b_2)h$, we can write:

Anew=116AoriginalA_{new} = \frac{1}{16} A_{original}

This equation shows that the new area is $ rac{1}{16}$ of the original area. The area is scaled by the square of the scaling factor, which in this case is $(\frac{1}{4})^2 = \frac{1}{16}$. This principle is fundamental in understanding how areas of scaled two-dimensional shapes are affected.

To illustrate this with a numerical example, let’s assume the original trapezoid has bases of 8 feet and 12 feet, and a height of 4 feet. The original area would be:

Aoriginal=12(8+12)×4A_{original} = \frac{1}{2} (8 + 12) \times 4

Aoriginal=12(20)×4=40 sq ftA_{original} = \frac{1}{2} (20) \times 4 = 40 \text{ sq ft}

After scaling by $ rac{1}{4}$, the new bases are 2 feet and 3 feet, and the new height is 1 foot. The new area would be:

Anew=12(2+3)×1A_{new} = \frac{1}{2} (2 + 3) \times 1

Anew=12(5)×1=2.5 sq ftA_{new} = \frac{1}{2} (5) \times 1 = 2.5 \text{ sq ft}

Comparing the new and original areas:

AnewAoriginal=2.540=116\frac{A_{new}}{A_{original}} = \frac{2.5}{40} = \frac{1}{16}

This confirms that the new area is $ rac{1}{16}$ of the original area, demonstrating the squared effect of the scaling factor on area. This relationship holds true regardless of the initial dimensions of the trapezoid, emphasizing the consistent mathematical principle governing area scaling.

True Statements Regarding the Scaled Trapezoid

Based on our analysis, we can now determine the true statements regarding the trapezoid scaled by a factor of $ rac{1}{4}$.

  • Statement A: The height of the new trapezoid will be 1 ft. This statement is true, as we demonstrated earlier. If the original height was 4 ft, scaling it by $ rac{1}{4}$ results in a new height of 1 ft.
  • Statement B: The height of the new trapezoid will be 16 ft. This statement is false. Scaling by $ rac{1}{4}$ reduces the height, not increases it.

To fully assess the statements, we need to consider additional information or context, particularly concerning the original dimensions of the trapezoid and the statements related to its area. If a statement claimed that