Vertex of x^2+2x-7=28

Aladder that is 30 ft long needs to reach 27 ft up a building. what should the angle of the vertical be?

Me! last question, and i'm stuck! write the algebraic expression that models the word phrase. the product of 2 divided by the number h and 8 more than the number k

Astudy was interested in determining if eating milk chocolate lowered someone's cholesterol levels. ten people's cholesterol was measured. then, each of these individuals were told to eat 100g of milk chocolate every day and to eat as they normally did. after two weeks, their cholesterol levels were measured again. is there evidence to support that their cholesterol levels went down? how should we write the alternative hypothesis? (mud = the population mean difference= before - after)a. ha: mud = 0b. ha: mud > 0c. ha: mud < 0d. ha: mud does not equal 0