What is the value of 12(8+9)

Determine whether the set of whole numbers is closed under addition. explain why the set is or is not closed. give an example.

Television sizes are based on the length of the diagonal of the television's rectangular screen. so, for example, a 70-inch television is a television having a diagonal screen length of 70 inches. if a 70 inch television's diagonal forms a 29°angle with the base of the screen, what is the vertical height (1) of the screen to the nearest inch? 70 inhin

1. are the corresponding angles congruent 2. find the ratios of the corresponding sides 3. is triangle jkl congruent to triangle rst? if so what is the scale factor