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Idrk what to put here but can someone help?

Idrk what to put here but can someone help?-example-1

2 Answers

4 votes

Check the picture below.

recall that the acute angles are complementary angles.


\tan(51^o )=\cfrac{\stackrel{opposite}{AC}}{\underset{adjacent}{7.3}} \implies 7.3\tan(51^o)=AC \implies \boxed{9.0\approx AC} \\\\[-0.35em] ~\dotfill\\\\ \cos(51^o )=\cfrac{\stackrel{adjacent}{7.3}}{\underset{hypotenuse}{AB}} \implies AB\cos(51^o)=7.3 \\\\\\ AB=\cfrac{7.3}{\cos(51^o)}\implies \boxed{AB\approx 11.6}

Make sure your calculator is in Degree mode.

Idrk what to put here but can someone help?-example-1
User Natsumi
by
8.1k points
5 votes

Answer:

The measure of Angle Ais
\sf \boxed{\sf \;\; 39 \;\; } degrees.

AC is
\boxed{ \;\;9.0\;\;} units long.

AB is
\boxed{\;\; 11.6 \;\;} units long.

Explanation:

In a right-angled triangle ABC, where C is the right angle, and B is an acute angle, we can use the trigonometric ratios to find the remaining sides and angles.

Given:


  • \sf C = 90^\circ

  • \sf B = 51^\circ

  • \sf BC = 7.3 (the side adjacent to angle B)

Find Angle A:

Since the sum of angles in a triangle is
\sf 180^\circ, we can find angle A using the equation:


\sf A + B + C = 180^\circ

Solve for angle A.


\sf A = 180^\circ - B - C


\sf A = 180^\circ - 51^\circ - 90^\circ


\sf A = 39^\circ

Find Side AC (the side opposite angle B):

Use the tangent ratio (
\sf \tan):


\sf \tan(B) = \frac{\textsf{Opposite}}{\textsf{Adjacent}}


\sf \tan(51^\circ) = (AC)/(BC)


\sf AC = BC \cdot \tan(51^\circ)


\sf AC = 7.3 \cdot \tan(51^\circ)


\sf AC \approx 9.014749243


\sf AC \approx 9.0 \textsf{(in 1 d.p.)}

Find Side AB (the hypotenuse):

Use the Pythagorean theorem:


\sf AB ^2 = AC^2 + BC^2


\sf AB = √(AC^2 + BC^2)


\sf AB = √((9.014749243)^2+ 7.3^2)


\sf AB = √(134.5557039)


\sf AB \approx 11.59981482


\sf AB \approx 11.6 \textsf{(in 1 d.p.)}

So, the remaining sides and angles are:

  • Angle A:
    \sf 39^\circ
  • Side AC:
    \sf \approx 9.166
  • Side AB:
    \sf \approx 11.572
Idrk what to put here but can someone help?-example-1
User Nrussell
by
8.0k points