In the picture there are two parabolas. One parabola can be mapped onto the other by shifting. These parabolas are graphs of the quadratic functions
\[ f(x)=-(x-a)^2+b\ \text{ and }\ g(x)=-(x-c)^2+d, \]
where \( a \), \( b \), \( c \), \( d\in\mathbb{R} \).
Following statements describe the relations between the pairs of the coefficients \( a \), \( b \), \( c \) and \( d \). Choose the true statement.