First degree equation;: A term that changes member changes sign Fractions: Multiply the 2 members by the nominators least common multiple

Got it !

$\LARGE (x+5)^2 - (x-5)^2 = 500$	$\LARGE 20x = 500 \qquad;\qquad x=\frac{500}{20} \qquad ;\qquad S =\{25\} $
$\LARGE (x-4)^2-5(16-x) = x(x-1)$	$\LARGE S = \{-32\} $
$\LARGE (x+2)(x+3) = x^2+366$	$\LARGE S = \{72\} $
$\LARGE 3x+100 = \frac{x}{3} +\frac{x}{2} -4$	$\LARGE 18x + 600 = 2x+3x-24 \qquad;\qquad S = \{-48\} \qquad;\qquad $Multiplication par 6 !
$\LARGE 3x-\frac{1}{2}(4-x)=x-\frac{1}{3}$	$\LARGE S = \{\frac{2}{3}\} $
$\LARGE 3x-\frac{1}{2}(\frac{x}{5}+6)=25+\frac{3x}{2}$	$\LARGE S = \{20\} $
$\LARGE \frac{5x-11}{4}-\frac{x-1}{10} = \frac{11x-1}{12}$	$\LARGE S = \{11\} $
$\LARGE \frac{5x-1}{7}- \frac{9x-7}{5} + \frac{9x-5}{11} = 0$	$\LARGE S = \{3\} $