What needs to happen before you can use the reason cpctc?

before you can use the reason CPCTC it must be stated that the triangles are congruente.

Explanation:

1) CPCTC stands for Corresponding Parts of Congruent Triangles are Congruent.

2) Therefore, to use that reason you first need to prove that the the triangles are congruent.

3) Once, it has been stated that the triangles are congruent, then you can use the reason to state the the corresponding segments are congruent which will let you to state the length of any side of one triangle known the corresponding side of the other triangle, because they are congruent (have the same length).

the law of definite proportions states samples of a compound will always contain the same proportion of elements by mass. in other words, a given compound will always contain the same elements in the same proportions by mass.the law of multiple proportions states when two elements combine with each other to form more than one compound, then the weights of one element that combine with a fixed weight of the other are in a ratio of small whole numbers.