Question

(6x+3y)(2x-Y+7) - 21(2x+y)​

Answer 1

Ответ:

12x²-3y²=0

Пошаговое объяснение:

12x²-6xy+42x+6xy-3y²+21y-42x-21y=0

сокращаем

остается 12x²-3y²=0

Answer 2

To simplify the expression (6x + 3y)(2x - y + 7) - 21(2x + y), you can use the distributive property to expand and combine like terms. Here's the step-by-step simplification:

1. Expand the first part of the expression: (6x + 3y)(2x - y + 7) = 6x(2x) + 6x(-y) + 6x(7) + 3y(2x) - 3y(y) + 3y(7)

2. Simplify each term: = 12x^2 - 6xy + 42x + 6xy - 3y^2 + 21y

3. Notice that the -6xy and 6xy terms cancel each other out.

4. Now, simplify further: = 12x^2 + 42x - 3y^2 + 21y

5. Factor out common factors, if possible: = 3(4x^2 + 14x - y^2 + 7y)

So, the simplified expression is 3(4x^2 + 14x - y^2 + 7y) - 21(2x + y).