Simply by adding like terms: -7x^2*y*z + 3y*z^2 - z*x^2*y - 4y

9514 1404 393

  -8x^2·y·z +3y·z^2 -4y

Step-by-step explanation:

It can be helpful to make sure the variables in each term are in alphabetical order. This makes it easier to see "like" terms. The variables in each term are ...

  x^2 y z

  y z^2

  x^2 y z

  y

Only the first and third terms are like terms, so those are the only ones that can be combined. Their coefficients are -7 and -1, so sum to -8. The combined term is of highest degree, so in standard form we list that term first.

  = -8x^2·y·z +3y·z^2 -4y

36 girls

step-by-step explanation:

the 48 boys is 4 parts of the ratio

divide 48 by 4 to obtain one part of the ratio

= 12 ← 1 part of the ratio

3 parts = 3 × 12 = 36 ← number of girls

the correct answer is $7.38

step-by-step explanation: