<span>Which expression is equivalent to x + y + x + y + 3(y + 5)? 2x + 5y + 5 2x + y + 30 2x + 5y + 15 2x + 3y + 10
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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°.


35 Percent of 70 is 24.5
We assume, that the number 70 is 100% - because it's the output value of the task. We assume, that x is the value we are looking for. If 70 is 100%, so we can write it down as 70=100%. We know, that x is 35% of the output value, so we can write it down as x=35%. <span>Now we have two simple equations: 1.)70=100% 2.)x=35%</span>where left sides of both of them have the same units, and both right sides have the same units, so we can do something like that: 70/x=100%/35% Now we just have to solve the simple equation, and we will get the solution we are looking for.
This question is asking you for the least common multiple of 60 (seconds in 1 minute) and 24 (seconds in 24 seconds).
I think it's 120 (you should check it) and that would be 3 minutes.