What about it? What is the question?
Let’s says that x is the measure of the angle. X and it’s supplement are equal to 180. X and it’s complement are equal to 90. The supplement is s and the complement is c. S is times c which is the same as 3c.
3c + x = 180
C+x = 90
X = 90 - c
3c + 90 - c = 180
2c = 90
C = 45
The complement of. 45 degree angle is 45 degrees.
The angle is 45 degrees.
The law of cosines for this particular situation is b^2 = a^2 + c^2 - 2ac cosB.
Filling in what you know, you have b^2 = 25 + 49 - [2(5)(7)-.1908], which simplifies to b^2 = 74 - 69.8092 which gives you a b^2 value of 4.1908, but you have to take the square root of that so you get a side value for b of 2.05.
63 in 4.5 hours
63 divided by 4.5 is 14 so
14 MPH would be your answer