Answer:
4
Step-by-step explanation:
using points (-4,-1) and (-4,3) put them into the equation.
[tex]\\\sqrt{(x_{2} -x_{1} )^{2} +(y_{2}-y_{1} )^{2} }[/tex]
[tex]\sqrt{((-4)-(-4))^{2}+ 3-(-1))^{2} }[/tex]
[tex]\sqrt{0+(3+1)^{2} }[/tex]
[tex]\sqrt{0+16}[/tex]
[tex]\sqrt{16}[/tex]
4
