Question

How can the area of this triangle be determined by forming a rectangle?

Select from the drop-down menus to correctly complete the statements.

Copy and rotate the triangle and place it next to the existing triangle to form a rectangle. The length of the rectangle is
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units. The width of the rectangle is
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units. The area of the rectangle is
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square units.

The area of the triangle is half the area of the rectangle, so the area of the triangle is
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square units.

Answer 1

Length of the rectangle = 5 units
Width of rectangle = 4 units

Area of rectangle = 20 units

Area of triangle = 10 units

Explanation:

Since I don't know the answer choices, I am assuming the base of the triangle as the length and the height as the width. Check your answer choices and switch 4 and 5 if it is the other way around

Using the graph

The rectangle formed by rotating the triangle and placing it along the original rectangle will have a length(base)
= length of the base of the triangle
= 5 units

The width of the rectangle will be the same as the height of the rectangle = 4 units

The area = length x width = 5 x 4 = 20 units

Area of triangle = half area of rectangle = 20/2 = 10 units