Answer:
By the definition and property of SAS similarity theorem
Explanation:
Similar triangles : If two triangles have two pairs of sides in the same ratio and the included angles are also equal, then the triangles are similar.
By definition of SAS i.e. side angle side, two triangles are congruent when the have two sides of one triangle is same with another triangle and have one same angle.
SAS Similarity Theorem state that If two sides in one triangle are proportional to two sides in another triangle and the included angle in both are congruent, then the two triangles are similar.
if we take any two triangle satisfying SAS property then it is easily proven by SAS similarity theorem that two triangles are similar.