$-7d+11=15$
Move the constant to the right-hand side and change its sign$-7d=15-11$
Subtract the numbers$-7d=4$
Divide both sides of the equation by $-7$$\begin{align*}&d=-\frac{ 4 }{ 7 } \\&d=-0.\overset{ \cdot }{ 5 } 7142\overset{ \cdot }{ 8 } \end{align*}$