<span><span>3+<span>xx</span></span>=19 </span>
<span /><span><span><span>x2</span>+3</span>=19 </span>
<span /><span>x2+3−3=<span>19 </span></span>
<span><span>−3</span></span><span><span><span><span><span>x2</span>=16</span></span></span></span>
<span><span><span><span /><span>x=<span>±<span>√16</span></span></span></span></span></span>
<span><span><span><span><span><span /></span></span></span></span></span>x = <span><span><span><span>4</span> or </span></span>x </span>= <span>−<span>4</span></span>
