Here are the first five terms of an arithmetic sequence. -1, 3, 7, 11, 15 Find, in terms of n, an expression for the nth term of this sequence.

In triangle abc segment de is parallel to the side ac . (the endpoints of segment de lie on the sides ab and bc respectively). find de, if ac=20cm, ab=17cm, and bd=11.9cm;

Use set buikder notation to represent the following set: {, -2, -1, 0}

Find the missing factor. write your answer inexponential form.9^2=9^4×