By which rule are these triangles congruent?

Idont get this question can someone me solve it? ** the distance light travels in one second (1 light second) is about 1.86 ×10^5 mi. saturn is about 475 light-seconds from the sun. about how many miles from the sun is saturn..my guess is 8.83* 10^7 you so much

Plz help plz give me the answer

Explain how you can use the associative property to evaluate (7x50)x4.