Respuesta :
Answer:
a) 11.4
Step-by-step explanation:
cos42=0.74
d²=c²+a²-2caCosD
d²=17²+13²-2×17×13×Cos42
d²=17²+13²-328.47
d²=289+169-328.47
d²=458-328.37
d=√129.63
d=11.4
The length of AC is 11.4 cm and the length of BC is 30.9 cm after solving through trigonometric ratios.
What are trigonometric ratios?
Trigonometric ratios deal with the sides and angles in a right angled triangle. sin, cos, tangent ,cosecant ,secant and cotangent are trigonometric ratios.
How to find the length of side of triangle?
ABC and ACD are triangle,
The value of AC will be:
According to cosine formula:
[tex]AC^{2} =AD^{2} +AC^{2} -2AD*AC*Cos D.[/tex]
[tex]AC^{2} =17^{2} +13^{2} -2*17*13* cos 42[/tex]
[tex]AC^{2} =[/tex]289+169-328.47
[tex]AC^{2}[/tex]=129.52
AC=11.4 cm
The value of BC will be as under:
using the sine rule
BC/sin A=CA/sin B=AB/sinC
BC/sin76=11.4/sin 21=AB/sin83
from the first 2 in equal to form
BC/sin 76=11.4/sin 21
BC=30.9
Hence the length of AC=11.4 cm and BC=30.9 cm.
Learn more about trigonometry at https://brainly.com/question/24349828
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