Find the vertex of y = x^2+ 2x + 8

What is the missing reason in step 5? linear pair postulategivendefinition of complementary anglescongruent complements theorem

Can someone me i’m confused. will give brainliest and a whole bunch of points

Amanda went into the grocery business starting with five stores. after one year, she opened two more stores. after two years, she opened two more stores than the previous year. if amanda expands her grocery business following the same pattern, which of the following graphs represents the number of stores she will own over time?