Una solución tiene un valor de pH=5 Cuál es la concentración molar de OH-?​

hope this .

r3t40

this may not be at all, but i use the same website you're using for school, and if i'm stuck doing one of these i try to look for it on the section.

ca = ec

cpctc makes it so that corresponding parts of the triangle you proved to be equal are equal, the other options aren't part of the part of the triangles you proved to be equal.