20 will mark supply the missing reasons to complete the proof.

In triangle  PRQ and triangle SRT

 [ANGLE]        [Given]

  [SIDE]     [Given]

  [ANGLE]      [Vertical angle are congruent]

ASA Postulate (Angle-Side-Angle): States that:

If two angles and the included side of one triangle are congruent to the corresponding parts of another triangle, then the triangles are congruent.

then, by the ASA postulates we can say that :

Corresponding parts of congruent triangles are congruent (CPCTC) means that two triangles are congruent if their corresponding sides are equal in length and their corresponding angles are equal in measure.

Then , by CPCT we have;

a function could be identified in 3 ways either on a chart,graph, or ordered pairs. first a function is that each point has its own. the rule is that there can be many x's to one y but there can not be 2 x's at different y's. so on a graph when you put a straight line through the y's there should be one dot only to be a function.

step-by-step explanation: