How do we solve for $x$ using law of sines?
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How do we solve for $x$ using the law of sines?
Here's my attempt:
$$angle BDC = 180- 30 - 12 = 138^circ$$
So we have that
$$dfrac{sin 30 }{|DC|} = dfrac{sin 12}{|DB|} = dfrac{sin 138}{|BC|} $$
For $triangle{ABD}$
$$dfrac{sin 18 }{|AD|} = dfrac{sin 24}{|DB|}$$
And what I need to evaluate is
$$dfrac{sin x }{|DC|} = ? $$
Can you help me take it from here?
trigonometry triangle
add a comment |
up vote
2
down vote
favorite
How do we solve for $x$ using the law of sines?
Here's my attempt:
$$angle BDC = 180- 30 - 12 = 138^circ$$
So we have that
$$dfrac{sin 30 }{|DC|} = dfrac{sin 12}{|DB|} = dfrac{sin 138}{|BC|} $$
For $triangle{ABD}$
$$dfrac{sin 18 }{|AD|} = dfrac{sin 24}{|DB|}$$
And what I need to evaluate is
$$dfrac{sin x }{|DC|} = ? $$
Can you help me take it from here?
trigonometry triangle
What else is valid for the triangle?
– greedoid
Nov 28 at 21:18
observe that $angle BDA =138^circ$
– Vasya
Nov 28 at 21:31
You can use Trigonometric form of Ceva's theorem to find $x$.
– Muralidharan
Nov 28 at 21:43
note that $180-24-18=138$, thus $angle ADB=138$. This gives $$angle ADC=84$$
– clathratus
Nov 28 at 21:50
I want to directly solve for $x$ using Sine law. Can anyone provide an answer if that's possible?
– Hamilton
Nov 29 at 13:25
add a comment |
up vote
2
down vote
favorite
up vote
2
down vote
favorite
How do we solve for $x$ using the law of sines?
Here's my attempt:
$$angle BDC = 180- 30 - 12 = 138^circ$$
So we have that
$$dfrac{sin 30 }{|DC|} = dfrac{sin 12}{|DB|} = dfrac{sin 138}{|BC|} $$
For $triangle{ABD}$
$$dfrac{sin 18 }{|AD|} = dfrac{sin 24}{|DB|}$$
And what I need to evaluate is
$$dfrac{sin x }{|DC|} = ? $$
Can you help me take it from here?
trigonometry triangle
How do we solve for $x$ using the law of sines?
Here's my attempt:
$$angle BDC = 180- 30 - 12 = 138^circ$$
So we have that
$$dfrac{sin 30 }{|DC|} = dfrac{sin 12}{|DB|} = dfrac{sin 138}{|BC|} $$
For $triangle{ABD}$
$$dfrac{sin 18 }{|AD|} = dfrac{sin 24}{|DB|}$$
And what I need to evaluate is
$$dfrac{sin x }{|DC|} = ? $$
Can you help me take it from here?
trigonometry triangle
trigonometry triangle
edited Nov 28 at 22:58
clathratus
2,735326
2,735326
asked Nov 28 at 21:14
Hamilton
1838
1838
What else is valid for the triangle?
– greedoid
Nov 28 at 21:18
observe that $angle BDA =138^circ$
– Vasya
Nov 28 at 21:31
You can use Trigonometric form of Ceva's theorem to find $x$.
– Muralidharan
Nov 28 at 21:43
note that $180-24-18=138$, thus $angle ADB=138$. This gives $$angle ADC=84$$
– clathratus
Nov 28 at 21:50
I want to directly solve for $x$ using Sine law. Can anyone provide an answer if that's possible?
– Hamilton
Nov 29 at 13:25
add a comment |
What else is valid for the triangle?
– greedoid
Nov 28 at 21:18
observe that $angle BDA =138^circ$
– Vasya
Nov 28 at 21:31
You can use Trigonometric form of Ceva's theorem to find $x$.
– Muralidharan
Nov 28 at 21:43
note that $180-24-18=138$, thus $angle ADB=138$. This gives $$angle ADC=84$$
– clathratus
Nov 28 at 21:50
I want to directly solve for $x$ using Sine law. Can anyone provide an answer if that's possible?
– Hamilton
Nov 29 at 13:25
What else is valid for the triangle?
– greedoid
Nov 28 at 21:18
What else is valid for the triangle?
– greedoid
Nov 28 at 21:18
observe that $angle BDA =138^circ$
– Vasya
Nov 28 at 21:31
observe that $angle BDA =138^circ$
– Vasya
Nov 28 at 21:31
You can use Trigonometric form of Ceva's theorem to find $x$.
– Muralidharan
Nov 28 at 21:43
You can use Trigonometric form of Ceva's theorem to find $x$.
– Muralidharan
Nov 28 at 21:43
note that $180-24-18=138$, thus $angle ADB=138$. This gives $$angle ADC=84$$
– clathratus
Nov 28 at 21:50
note that $180-24-18=138$, thus $angle ADB=138$. This gives $$angle ADC=84$$
– clathratus
Nov 28 at 21:50
I want to directly solve for $x$ using Sine law. Can anyone provide an answer if that's possible?
– Hamilton
Nov 29 at 13:25
I want to directly solve for $x$ using Sine law. Can anyone provide an answer if that's possible?
– Hamilton
Nov 29 at 13:25
add a comment |
2 Answers
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up vote
1
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This works if you know what $|BC|$ and $|AC|$ are.
$$frac{sin(x+24)}{|BC|}=frac{sin48}{|AC|}$$
$$sin(x+24)=frac{|BC|sin48}{|AC|}$$
$$x+24=arcsinbigg(frac{|BC|sin48}{|AC|}bigg)$$
$$x=arcsinbigg(frac{|BC|sin48}{|AC|}bigg)-24$$
add a comment |
up vote
0
down vote
Recall that the angles of a triangle must add up to 180°. From this we can conclude that angle $CDB$ measures 138° and angle $BDA$ measures 138°. Therefore angle $ADC$ measures 84°. Now, if we let $y$ be the measure of angle $DCA$ (in degrees), we have the following system of equations.
$$ begin{array}{rcr} x + y + 84 & = & 180 \ x + y + 84 & = & 180 end{array} $$
So I want to say there will be infinitely many solutions... apparently there is some freedom in choosing the sides, as the other answer has hinted. But not 100% sure. Anyone else want to weigh in?
add a comment |
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2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
up vote
1
down vote
This works if you know what $|BC|$ and $|AC|$ are.
$$frac{sin(x+24)}{|BC|}=frac{sin48}{|AC|}$$
$$sin(x+24)=frac{|BC|sin48}{|AC|}$$
$$x+24=arcsinbigg(frac{|BC|sin48}{|AC|}bigg)$$
$$x=arcsinbigg(frac{|BC|sin48}{|AC|}bigg)-24$$
add a comment |
up vote
1
down vote
This works if you know what $|BC|$ and $|AC|$ are.
$$frac{sin(x+24)}{|BC|}=frac{sin48}{|AC|}$$
$$sin(x+24)=frac{|BC|sin48}{|AC|}$$
$$x+24=arcsinbigg(frac{|BC|sin48}{|AC|}bigg)$$
$$x=arcsinbigg(frac{|BC|sin48}{|AC|}bigg)-24$$
add a comment |
up vote
1
down vote
up vote
1
down vote
This works if you know what $|BC|$ and $|AC|$ are.
$$frac{sin(x+24)}{|BC|}=frac{sin48}{|AC|}$$
$$sin(x+24)=frac{|BC|sin48}{|AC|}$$
$$x+24=arcsinbigg(frac{|BC|sin48}{|AC|}bigg)$$
$$x=arcsinbigg(frac{|BC|sin48}{|AC|}bigg)-24$$
This works if you know what $|BC|$ and $|AC|$ are.
$$frac{sin(x+24)}{|BC|}=frac{sin48}{|AC|}$$
$$sin(x+24)=frac{|BC|sin48}{|AC|}$$
$$x+24=arcsinbigg(frac{|BC|sin48}{|AC|}bigg)$$
$$x=arcsinbigg(frac{|BC|sin48}{|AC|}bigg)-24$$
answered Nov 28 at 21:57
clathratus
2,735326
2,735326
add a comment |
add a comment |
up vote
0
down vote
Recall that the angles of a triangle must add up to 180°. From this we can conclude that angle $CDB$ measures 138° and angle $BDA$ measures 138°. Therefore angle $ADC$ measures 84°. Now, if we let $y$ be the measure of angle $DCA$ (in degrees), we have the following system of equations.
$$ begin{array}{rcr} x + y + 84 & = & 180 \ x + y + 84 & = & 180 end{array} $$
So I want to say there will be infinitely many solutions... apparently there is some freedom in choosing the sides, as the other answer has hinted. But not 100% sure. Anyone else want to weigh in?
add a comment |
up vote
0
down vote
Recall that the angles of a triangle must add up to 180°. From this we can conclude that angle $CDB$ measures 138° and angle $BDA$ measures 138°. Therefore angle $ADC$ measures 84°. Now, if we let $y$ be the measure of angle $DCA$ (in degrees), we have the following system of equations.
$$ begin{array}{rcr} x + y + 84 & = & 180 \ x + y + 84 & = & 180 end{array} $$
So I want to say there will be infinitely many solutions... apparently there is some freedom in choosing the sides, as the other answer has hinted. But not 100% sure. Anyone else want to weigh in?
add a comment |
up vote
0
down vote
up vote
0
down vote
Recall that the angles of a triangle must add up to 180°. From this we can conclude that angle $CDB$ measures 138° and angle $BDA$ measures 138°. Therefore angle $ADC$ measures 84°. Now, if we let $y$ be the measure of angle $DCA$ (in degrees), we have the following system of equations.
$$ begin{array}{rcr} x + y + 84 & = & 180 \ x + y + 84 & = & 180 end{array} $$
So I want to say there will be infinitely many solutions... apparently there is some freedom in choosing the sides, as the other answer has hinted. But not 100% sure. Anyone else want to weigh in?
Recall that the angles of a triangle must add up to 180°. From this we can conclude that angle $CDB$ measures 138° and angle $BDA$ measures 138°. Therefore angle $ADC$ measures 84°. Now, if we let $y$ be the measure of angle $DCA$ (in degrees), we have the following system of equations.
$$ begin{array}{rcr} x + y + 84 & = & 180 \ x + y + 84 & = & 180 end{array} $$
So I want to say there will be infinitely many solutions... apparently there is some freedom in choosing the sides, as the other answer has hinted. But not 100% sure. Anyone else want to weigh in?
answered Nov 29 at 11:40
Nikifuj908
635
635
add a comment |
add a comment |
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What else is valid for the triangle?
– greedoid
Nov 28 at 21:18
observe that $angle BDA =138^circ$
– Vasya
Nov 28 at 21:31
You can use Trigonometric form of Ceva's theorem to find $x$.
– Muralidharan
Nov 28 at 21:43
note that $180-24-18=138$, thus $angle ADB=138$. This gives $$angle ADC=84$$
– clathratus
Nov 28 at 21:50
I want to directly solve for $x$ using Sine law. Can anyone provide an answer if that's possible?
– Hamilton
Nov 29 at 13:25