Answer:
18 units
Step-by-step explanation:
(-4 , 10) and (-4, -8)
Distance = [tex]\sqrt{(x_{2}+x_{1})^{2}+(y_{2}-y_{1})^{2}}\\[/tex]
[tex]= \sqrt{(-4-[-4])^{2}+(-8-10)^{2}}\\\\= \sqrt{(-4+4)^{2}+(-18)^{2}}\\\\=\sqrt{0 + 324}\\\\=\sqrt{324}\\\\= 18[/tex]