# From negative to positive

Geometry Level 4

$\sin{(x-y)}=\cos{(x-y)} , \quad \text{ and } \quad \sin{(x+y)}=\cos{(x+y)}$

Consider the graphs of the equations. Hummus (me) wanted one single equation to represent both graphs.

If the equation Hummus found is in the form $$\cos{(ax)}=\sin{(ay)}$$, find $$a$$.

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