Can a triangle have the sides with the given lengths? \( \begin{array}{l}\text { 18. } 8 \text { in., } 7 \mathrm{in}, 9 \mathrm{in} . \\ \text { List the angles of the triangle in order from smallest to biggest. } \\ \text { 20. }\end{array} \) (19.7 \( \mathrm{ft},. 6 \mathrm{ft} \).

To determine if a triangle can be formed with the sides 18.8 in, 7 in, and 9 in, we can use the triangle inequality theorem, which states that the sum of the lengths of any two sides must be greater than the length of the third side. Here, the pairwise sums are: 1) 18.8 + 7 = 25.8 > 9, 2) 18.8 + 9 = 27.8 > 7, 3) 7 + 9 = 16 > 18.8. The last inequality fails, so these sides cannot form a triangle. If we had valid side lengths and could form a triangle, we would use the Law of Cosines to find the angles. Given valid sides \(a\), \(b\), and \(c\), we'd calculate angles as follows: for \(\angle A\) opposite side \(a\), \(\angle B\) opposite side \(b\), and \(\angle C\) opposite side \(c\). Then, we could sort them in ascending order to find the sequence.