Thực hiện phép tính(3x-5y)(4x+7y)

(3x - 5y)(4x + 7y) =

3x × 4x + 3x × 7y - 5y × 4x - 5y × 7y =

12x² + 21xy - 20xy - 35y² =

12x² + xy - 35y²

12x^2 + 1xy -35y^2

Step-by-step explanation:

12x^2 + 21xy -20xy -35y^2 becomes this simplified

answer: it would most likely be y=6 and 5/7.

step-by-step explanation:

question 1 is 8, question 2 is 9, question 3 is 24

step-by-step explanation:

now, the numbers they give you at the top are the key. from there, you just have to plug and chug! let's try 1, 2, and 3!

key: a=3, b=5, c=6

1. a+5

remember, a=3, so we plug that in to get 3+5=8

2. 15-c

c=6, so we plug that in to get 15-6=9

3. 4b

b=6, so we plug it in to get 4*6=24

time to try the rest on your own! if you put the answers below in a comment, i'll check them for you!