When deriving the quadratic formula by completing the square what expression can be added to both sides of the equation to create a perfect square trinomial x^+b/ax+_=-c/a+_

Ineed with number 17 i don’t get it at alll

Ms. sutton recorded the word counts and scores of the top ten essays in a timed writing contest. the table shows her data. how does the word count of an essay relate to its score in the contest? word count tends to decrease as the score decreases. word count tends to increase as the score decreases. word count tends to remain constant as the score decreases. word count has no apparent relationship to the score of the essay.

Some boys and girls were asked if they had a pet. one third of the group were boys. there were 20 boys. 20% of the girls had a pet. boys with a pet : girls with a pet = 1 : 5 i need to know how many girls there are.