Help!! quickly its a test

How do you determine whether a relationship represented as as graph is linear or nonlinear

Manuela claims that and are congruent. which statement best describes her claim? she is incorrect because the segments do not have the same orientation. she is incorrect because the segments do not have the same length. she is correct because the segments have the same length. she is correct because the segments have the same orientation.

Grant simplified the expression 1.5(-3.2 + 2.5) his work is shown below explain the error in grants work