Respuesta :
Answer:
To the nearest tenth = 10.8cm
Step-by-step explanation:
Using the cosine rule
J² = i² + k² + 2ikcosj
J² = 3.4² + 7.7² + 2(3.4)(7.7) cos 30
J² = 11.56 + 59.29 + 52.36cos30
J² = 11.56 + 59.29 + 52.36(0.8660)
J² = 11.56 + 59.29 + 45.35
J² = 116.2
J=√116.2
J= 10.78 cm
To the nearest tenth = 10.8cm
Answer:
its 5.1
Step-by-step explanation:
\text{S.A.S.}\rightarrow \text{Law of Cosines}
S.A.S.→Law of Cosines
a^2=b^2+c^2-2bc\cos A
a
2
=b
2
+c
2
−2bccosA
From reference sheet.
j^2 = 7.7^2+3.4^2-2(7.7)(3.4)\cos 30
j
2
=7.7
2
+3.4
2
−2(7.7)(3.4)cos30
Plug in values.
j^2 = 59.29+11.56-2(7.7)(3.4)(0.866025)
j
2
=59.29+11.56−2(7.7)(3.4)(0.866025)
Square and find cosine.
j^2 = 59.29+11.56-45.34509
j
2
=59.29+11.56−45.34509
Multiply.
j^2 = 25.50491
j
2
=25.50491
Add.
j=\sqrt{25.50491} \approx5.05 \approx5.1
j=
25.50491
≈5.05≈5.1
Square root and round.
