In which triangle is the value of [tex]\( x \)[/tex] equal to [tex]\( \cos^{-1}\left(\frac{4.3}{6.7}\right) \)[/tex]?

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Answer :

To determine which triangle has the value of [tex]\( x \)[/tex] such that [tex]\( x = \cos^{-1}\left(\frac{4.3}{6.7}\right) \)[/tex], let's follow a detailed, step-by-step approach:

1. Understand the relationship: The expression [tex]\( \cos^{-1}\left(\frac{4.3}{6.7}\right) \)[/tex] refers to the angle whose cosine value is [tex]\( \frac{4.3}{6.7} \)[/tex].

2. Calculate the ratio:
[tex]\[ \frac{4.3}{6.7} \approx 0.6418 \][/tex]

3. Determine angle [tex]\( x \)[/tex]: The inverse cosine function, [tex]\( \cos^{-1} \)[/tex], gives us an angle whose cosine is the given ratio. Let's denote this angle by [tex]\( x \)[/tex].

4. Find the measure of angle [tex]\( x \)[/tex]:
[tex]\[ x \approx \cos^{-1}(0.6418) \approx 0.874 \text{ radians} \][/tex]

5. Convert radians to degrees: To better interpret this angle in a triangle, we convert it from radians to degrees,
[tex]\[ x \approx 0.874 \text{ radians} \times \left(\frac{180}{\pi}\right) \approx 50.074 \text{ degrees} \][/tex]

6. Interpretation: Now, we know that the angle [tex]\( x \)[/tex] in the triangle is approximately [tex]\( 50.074 \)[/tex] degrees.

In summary:
- The ratio of the sides is [tex]\( \frac{4.3}{6.7} \approx 0.6418 \)[/tex].
- The angle [tex]\( x \)[/tex] corresponding to [tex]\( \cos^{-1}(0.6418) \)[/tex] is approximately [tex]\( 0.874 \)[/tex] radians.
- Converting [tex]\( 0.874 \)[/tex] radians to degrees, [tex]\( x \approx 50.074 \)[/tex] degrees.

Thus, in the triangle, the value of [tex]\( x \)[/tex] is approximately [tex]\( 50.074 \)[/tex] degrees. The triangle where one of the angles is [tex]\( 50.074 \)[/tex] degrees is the one that we're looking for.