Solve the triangle, given the following : angle A= 30, side b= 6 , and side c=8 find angle C, Angle B, and side a?
well the triangle looks like |dw:1417848762923:dw| find a by using the law of cosines then find B using the law of Sines then find C using angle sum of a triangle hope it helps
a=9.2 , i tried to use law of sine , but the answer didn't make sense
sinB/6 = sine30/9.23 ..... couldn't get a realistic solution from it
the law of sines says \[\frac{\sin(30)}{9.2} = \frac{\sin(B)}{6}\]
so \[\sin(B) = \frac{6 \times \sin(30)}{9.2}\] you will get a decimal less than 1... then its \[B = \sin^{-1}(answer) \]
and you may like to check your solution to a
I got a negative solution, won't that be undefined .. because the limit is 0-1?
ok.... go back to the law of cosines \[a^2 = 6^2 + 8^2 - 2 \times 6 \times 8 \times \cos(30)\]
by my calculations its not 9.2
if you look at the triangle the angle of 30 is opposite the longest side 9.2 so B and C would need to be less than 30... so its not a triangle
still there @moonlight93
so would that be "can not be solved" ?
no... go back and redo the law of cosines... as your answer is incorrect for a I posted it correctly above...
I still don't get it. i've been trying over and over. do you know the answer of angle B ?
ok... \[a^2 = 6^2 + 8^2 - 2 \times 6 \times 8 \times \cos(30)\] \[a^2 = 100 - 83.14\] what is the value of a...?
a=4.106
but why did you get a 83.14 for the right side? I got 100-14.808 ... and that's how I got the 9.23
great... so now the measurements make sense then \[\frac{\sin(30)}{4.1} = \frac{\sin(B)}{6}\] so sin(B) = 0.731717
so then \[B = \sin^{-1}(0.731707)\] then find C using angle sum of a triangle.
83.2....= 2 x 6 x 8 cos(30)
I have to go... Hope its helped.
ok, thank you
@@ is your triangle even a right triangle?
@campbell_st ... sorry yes it will equal 83.2 .. my calculator was in radians mode, I got that answer when i swiched to degree mode. thank you for helping :)
@BabiiMuffin , it doesn't say it is. we've been studying both non-right and right triangle.. though we suppose to solve as if it's a non-triangle.
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