Which congruence theorem, if any can be used to prove that the triangles are congruent?

What is the size of the matrix resulting from

The angle of a triangle are given as 6x,(x-3), and (3x+7). find x then find the measures of the angles

Asurvey of 45 teens found that they spent an average of 25.6 hours per week in front of a screen (television, computer, tablet, phone, based on the survey’s sample mean, which value could be the population mean? 2.3 hours 27.4 hours 75.3 hours 41.5 hours