[tex]\boxed{-2\left(z+5\right)+20>6\quad :\quad \begin{bmatrix}\mathrm{Solution:}\:&\:z<2\:\\ \:\mathrm{Interval\:Notation:}&\:\left(-\infty \:,\:2\right)\end{bmatrix}}[/tex]
Solution:
Given inequality is:
[tex]-2(z+5)+20>6[/tex]
We have to solve the given inequality
[tex]-2\left(z+5\right)+20>6\\\\\mathrm{Subtract\:}20\mathrm{\:from\:both\:sides}\\\\-2\left(z+5\right)+20-20>6-20\\\\\mathrm{Simplify}\\\\-2\left(z+5\right)>-14[/tex]
[tex]Multiply\ both\ sides\ by\ -1\ \left(reverse\:the\:inequality\right)[/tex]
Whenever we multiply or divide an inequality by a negative number, we must flip the inequality sign
[tex]\left(-2\left(z+5\right)\right)\left(-1\right)<\left(-14\right)\left(-1\right)\\\\\mathrm{Simplify}\\\\2\left(z+5\right)<14\\\\\mathrm{Divide\:both\:sides\:by\:}2\\\\\frac{2\left(z+5\right)}{2}<\frac{14}{2}\\\\\mathrm{Simplify}\\\\z+5<7\\\\\mathrm{Subtract\:}5\mathrm{\:from\:both\:sides}\\\\z+5-5<7-5\\\\simplify\ the\ above\\\\\boxed{z < 2 }[/tex]
Thus the solution to inequality is:
[tex]-2\left(z+5\right)+20>6\quad :\quad \begin{bmatrix}\mathrm{Solution:}\:&\:z<2\:\\ \:\mathrm{Interval\:Notation:}&\:\left(-\infty \:,\:2\right)\end{bmatrix}[/tex]