For the tringle shown what are the :

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SUMMARY

The discussion centers on the correct application of the Pythagorean theorem and trigonometric functions in triangle calculations. The user initially states the formula as "c = a2 - b2," which is incorrect; the correct formulation is "c² = a² - b²." The calculations for the sides and angles of the triangle are also misrepresented, particularly in the interpretation of tangent and sine functions. The correct approach involves using "c = √(81 - 49)" for side length and "Q = arctan(2/7)" for angle calculation.

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For the tringle shown what are the :



my answer :



a )c = a2 - b2

81 - 49 = root 32



b ) tan Q = 2/7 = 0.28



C ) the angle sin = 9/7 = 1.28
 

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First of all, please be a bit more careful with the notation.
In "c = a2 - b2" I assume that the "2"s mean: square, which is not a priori clear form the context (you could use a^2 or a2 or [itex]a^2[/itex] instead). Then I suppose you want to use the Pythagorean theorem, which is not
c = a2 - b2
but
c2 = a2 - b2.

Also, 81 - 49 = 32, not root(32) = 5.65685... What I suppose you wanted to say is, c2 = 81 - 49 = 32, so c = root(32).

In the picture, you have two angles labeled Q. However, these angles are not equal (that would mean the triangle is isoscles, but having sides of three different lengths that is not the case). So which one do you mean?

Also, how do you get tan(Q) = 2 / 7? Even if you pick one of the angles Q, I don't see a side of length 2.

For c) I think you are supposed to invert the tangent function (if tan(Q) = a, then Q = arctan(a)).
"sin = 9/7" does not mean anything (the sine of what?)
 

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