A question about the justification behind the solution of a problem. (1 Viewer)

[Gods_Spear]

Part i and ii are fine and I managed to solve them, but for part iii i had to go to the solutions. I don't understand why the gradient of AC is tan45, I feel I'm missing something simple and am being a dumbass but I dont get it.

 

[kkk579]

Its because gradient is rise over run or just change in y over change in x. And the formula for tantheta = opposite/adjacent, which is legit just rise/run. Thats why tan45 is the gradient of AC

 

[wizzkids]

Actually in the solution it would have been quicker to state the law of triangles, sum of the interior angles must be 180^o and therefore the gradient of the line CB must be -1.