What should be added to x²+xy+y² to obtain 2x+3y​

So x^2 + 2xy - y^2

Step-by-step explanation:

Let "a" be added to x^2 + xy +y^2 to obtain 2x^2 + 3xy

So a = 2x^2 + 3xy - (x^2 + xy + y^2)

= 2x^2 + 3xy - x^2 -xy - y^2

= x^2 + 2xy - y^2.

So x^2 + 2xy - y^2 must be added.

answer: the dogs need to shift their focus to human scent.

its because the dogs being trained are for search and rescue thus they need to be able to track humans and their specific scent

walter needs to make at least 5 more cookies but no more than 40. 5 ≤ x ≤ 40

step-by-step explanation:

20 ≤ x + 15 ≤ 55

subtract 15 from all parts

20-15 ≤ x + 15-15 ≤ 55-15

5 ≤ x ≤ 40

this means how many more cookies he has to make

walter needs to make at least 5 more cookies, but no more than 40 cookies; 5 ≤ x ≤ 40