√50 + √242 - √2
= √5·5·2 + √11·11·2 -√2
= 5√2 + 11√2 - √2
= 16√2 - √2
= 15√2
This is adding two vectors, one magnitude 300 direction east, and one magnitude 100 direction 30 degrees northeast.
For the resulting sum we can use the Law of Cosines or just add up the components. Let's try it both ways.
Components first. In the east direction we have
300 + 100 cos 30° = 300 + 100(√3/2) = 386.60 miles per hour
In the north direction we have
0 + 100 sin 30° = 100 (1/2) = 50 miles per hour
So a total speed of
sqrt{386.6^2 + 50^2} = 389.82 miles per hour
Answer: 389.82
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OK let's try the Law of Cosines. We have sides 300 and 100 and included angle 150°.


Subtract 3 both sides first. R-3=ts²
next, divide both sides by t, (R-3)/t=s²
finally, take the square root of both sides
√(R-3)/t = s. 2nd choice.
Answer:
Min:3 Q:66-9 Med:9 Q3:10-14 Max19
Answer: x=18
im assuming that this is a right angle
so if it is then that means the total of the angle should be 90 degrees. so 2x+3x should be equal to 90. Just combine like terms to get that 5x=90 and then isolate the variable (divide by 5 on both sides) so x ends up equaling 18.
so x=18