C. 1/root2
Based on the information, the hypotenuse will be 6root2 because it is a 45, 45, 90 triangle. The two legs will be 6. Using SOH CAH TOA, we know that for cosine, it will be adjacent/hypotenuse. The adjacent side is 6 and the hypotenuse is 6root2. The result will be (6)/(6root2). After simplifying, we get
1/root2.
43 not 100% shure good luck
Here’s a written work of the question hope this helps
Because we know that the number in between x+6 and 2x-3 is 18, we can solve for x by doing (x+6+2x-3)/2=18. this simplifies to 3x+3=36, or x=11.