<span>30 + 2 + 0.04 + 0.003</span>
<span>3x^2−2x+7=0
</span>3x^2−2x+1/3+7−1/3=<span>0
</span><span>3<span>(x^2−2x/3+1/9)</span>+7−1/3=0
</span><span>3<span><span>(x−1/3)^</span>2</span>+(21−1)/3=0
</span><span>3<span><span>(<span>x−1/3</span>)^</span>2</span>=−<span>20/3
</span></span><span><span>(<span>x−<span>1/3</span></span>)^</span>2</span>=−<span>20/9</span>
