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Pls help thx (dont guess pls)

Pls help thx (dont guess pls)-example-1
User Liwen
by
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2 Answers

2 votes

Answer:

UV = 10, ∠ UCT = 44° , ∠ UAV = 20°

Explanation:

• the incentre (V) is equally distant from the triangles three sides

Then

UV = SV = 10

The angle bisector VC , splits ∠ UCT into 2 equal parts

Then

∠ UCT = 2 × ∠ UCV = 2 × 22° = 44°

the sum of the 3 angles in Δ ABC = 180° , that is

∠ SAU + ∠ SBT + ∠ UCT = 180° ( substitute values )

∠ SAU + 96° + 44° = 180°

∠ SAU + 140° = 180° ( subtract 140° from both sides )

∠ SAU = 40°

Since VA bisects ∠ SAU

Then

∠ UAV =
(1)/(2) × ∠ SAU =
(1)/(2) × 40° = 20°

User Swasidhant
by
8.4k points
2 votes

1. UV:
\(UV \approx 10 + 13 \cdot \tan(84^\circ) + 0.92 \cdot \tan(22^\circ) \cdot (\tan(42^\circ) \cdot (s - 13))\).

2.
\(m\angle UCT\): \(m\angle UCT \approx 54^\circ\).

3.
\(m\angle UAV\): \(m\angle UAV = 84^\circ\).


Let's denote the angles as follows:


- \(\angle AVB = \alpha\),- \(\angle AVC = \beta\),- \(\angle BVC = \gamma\).

We are given that
\(m\angle SBT = 96^\circ\) and \(m\angle UCV = 22^\circ\). Since \(BT\) and \(UC\) are angle bisectors, we can find that \(\angle SBU = \angle UBV = \alpha/2\) and \(\angle UCB = \angle VCU = \beta/2\).

Now, let's find
\(\angle SBV\):


\[m\angle SBV = m\angle SBU + m\angle UBV = (\alpha)/(2) + (\alpha)/(2) = \alpha.\]

Similarly, let's find
\(\angle UCV\):


\[m\angle UCV = m\angle UCB + m\angle VCU = (\beta)/(2) + (\beta)/(2) = \beta.\]

Now, we have the following information:


- \(m\angle SBV = \alpha\),- \(m\angle UCV = \beta\),- \(m\angle SBT = 96^\circ\),- \(m\angle UCV = 22^\circ\).

Since
\(\angle SBV + \angle UCV + \angle SBT = 180^\circ\) in a triangle, we can write the equation:


\[\alpha + \beta + 96^\circ = 180^\circ.\]

Solving for
\(\alpha + \beta\):


\[\alpha + \beta = 180^\circ - 96^\circ = 84^\circ.\]

Now, let's find
\(\angle UBV\) and
\(\angle UCB\) using the fact that they are half of
\(\alpha\) and
\(\beta\), respectively:


\[\angle UBV = (\alpha)/(2) = (84^\circ)/(2) = 42^\circ,\]\[\angle UCB = (\beta)/(2) = (84^\circ)/(2) = 42^\circ.\]

Finally, we have:

-
\(UV = SV + SU = SV + BV \tan(\angle SBV) + CV \tan(\angle UCV),\)

-
\(m\angle UCT = 180^\circ - \angle UCB - \angle UCV,\)

-
\(m\angle UAV = \angle UBV + \angle UCB.\)

1. UV:


\[UV = 10 + 13 \tan(84^\circ) + \tan(22^\circ) \cdot (\tan(42^\circ) \cdot (s - 13)).\]

First, calculate
\(s\) and
\(a\):


\[s = (13 + CV + BC) / 2\]


\[a = 13.\]

Substitute these values into the expression for UV:


\[UV = 10 + 13 \tan(84^\circ) + \tan(22^\circ) \cdot (\tan(42^\circ) \cdot (s - 13)).\]

Using a calculator, we find that
\(UV \approx 10 + 13 \cdot \tan(84^\circ) + \tan(22^\circ) \cdot (\tan(42^\circ) \cdot (s - 13)) \approx 10 + 13 \cdot 11.43 + 0.92 \cdot (\tan(42^\circ) \cdot (s - 13))\).

2.
\(m\angle UCT\):


\[m\angle UCT = 180^\circ - 42^\circ - 84^\circ.\]

Therefore,
\(m\angle UCT = 180^\circ - 42^\circ - 84^\circ \approx 54^\circ.\)

3.
\(m\angle UAV\):


\[m\angle UAV = 42^\circ + 42^\circ.\]

Therefore,
\(m\angle UAV = 42^\circ + 42^\circ = 84^\circ.\)

User Kasumi
by
7.7k points