Can anyone explain to me why it is 7.5？？

[10 points, algebra 2-simplifying complex fractions]according to my answer key the restrictions are -1 and 4. but why not positive 1?

In the diagram, the ratios of two pairs of corresponding sides are equal to prove that almn - axyz by the sas similarity theorem, it also needs to be shown that x 6 z un z zz un = 2x zləzz lezy

Jennifer taking a quiz and has answered 13 questions so far. if there are 25 questions on jennifer test, how many questions does she have left to answer