TeX source:

\mathrm{C}=3000 \operatorname{dist}(\mathrm{C}, \mathrm{W})+7000 \operatorname{dist}(\mathrm{W}, \mathrm{D})=3000 \sqrt{\mathrm{x}^{2}+9}+7000 \sqrt{(10-\mathrm{x})^{2}+25}