Question 1038537

Solve http://prntscr.com/bhzilv Justify each step in your solution
<pre>{{{8sqrt(4*z^2 - 43) = 40}}}
{{{sqrt(4*z^2 - 43) = 5}}} -------- Dividing each side by 8
{{{(sqrt(4z^2 - 43))^2 = 5^2}}} ---- Squaring each side
{{{4z^2 - 43 = 25}}}
{{{4z^2 = 68}}} ------- Adding 43 to both sides
{{{z^2 = 68/4}}}
{{{z^2 = 17}}}
{{{highlight_green(z = " "+- sqrt(17))}}}