Consider using the Law of Cosines, because the lengths of three sides are given and the largest angle is the one to be approximated. This angle will be opposite the longest side, that is, opposite the 420-foot side.
420^2 = 250^2 + 300^2 - 2(250)(300)cos A.
Then: 176400 = 62500 + 810000 - 150000cos A.
Solving for cos A, we get:
150000cos A = 176400-62500-810000, or -696100
Then:
-696100
cos A = ------------------- = - 4.64. This is not possible, as the range of the cosine
150000 function is [-1,1].
Given:
Two vectors (u) and (w) and the angle between them θ

the sketch of the vectors will be as shown in the following figure:
As shown, the resultant vector is the blue line segment
The vector R has a magnitude = 60.22
And the angle between u and R = 5.56°
Answer: A reflection across the x-axis keeps the x-coordinates the same but flips the signs of the y-coordinates. So, it should be the opposite for a reflection across the y-axis. The y-coordinates remain the same, but the signs of the x-coordinates change.
Step-by-step explanation
I copy and pasted the answer
The answer is
a) 11/15
b) 1/18