1. (a+7) (a-b) = 2. (x-3) (x-7)= 3. (5x-2) (x14)= 4. (4x-2) (4x-2) = 5. (5a-2b) (a+b) = Tolong dibjawab!

1. ( a+7)(a-b)= a²-ab+7a - 7b
2. (x-3)(x-7) = x²+10x+21
3. (5x-2)(x-14) = 5x²-72x+28
4. (4x-2)(4x-2) = 16x² -16x+4
5. (5a-2b)(a+b) = 5a² +3ab -2b²

1.
(a + 7) (a - b) = a² + 7a - ab - 7b

2.
(x - 3) (x - 7) = x² - 10x + 21

3. ??

4.
(4x - 2) (4x - 2) = 16x² - 16x + 4

5.
(5a - 2b) (a + b) = 5a² + 3ab - 2b²

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(a + b) (c + d)
= a(c + d) + b(c + d)
= ac + ad + bc + bd