Question

Question 9
$3(5z-7)-2(9z-11)=4(8z-13)-17$

Answer 1

$3(5z-7)-2(9z-11)=4(8z-13)-17\Rightarrow 15z-21-18z+22=32Z-52-17$
$\Rightarrow -3z+1=32z-69\Rightarrow -3z-32z=-69-1$
$\Rightarrow -35z=-70$
$z=2$
To check:
$3(5z-7)-2(9z-11)=4(8z-13)-17$
$\Rightarrow 3(5\times 2-7)-2(9\times 2-11)=4(8\times 2-13)-17$
$\Rightarrow 3(10-7)-2(18-11)=4(16-13)-17$
$\Rightarrow 3\times 3-2\times 7=4\times 3-17\Rightarrow 9-14=12-17$
$\Rightarrow -5=-5$
$\Rightarrow L.H.S.=R.H.S$
Therefore, it is correct.