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The length of the longer base of an iscocoles trapezoid is 12 cm. the length of each side is 5 cm. The acute angle is 37º. Find the shorter base.

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Final Answer:

The length of the shorter base is approximately 7.23 cm.

Step-by-step explanation:

Identify relevant information:

Longer base length (BL) = 12 cm

Side length (S) = 5 cm

Acute angle (θ) = 37°

Formulate a relationship between the sides:

We can utilize the Pythagorean theorem on the right triangle formed by the longer base, the side, and the hypotenuse (which is also the longer base in an isosceles trapezoid):

BL^2 = 2 * S^2

Substitute known values and solve for S:

12^2 = 2 * 5^2

S^2 = 12^2 / 2

S ≈ 7.23 cm

Calculate the shorter base length:

Since the base angles are congruent, we can apply the sine rule on the smaller right triangle formed by the shorter base, the side, and the acute angle:

S / sin(θ) = BL / sin(90° - θ)

Substitute and solve for the shorter base:

7.23 / sin(37°) = 12 / sin(90° - 37°)

Shorter Base ≈ 7.23 cm

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