11.(7x+8y)(8y-7x), 12.(A+B+C)(A+B-C), 13.(X+Y)-1(X+Y)+1, 14.(2x+Y)-Z)(2x+Y)+, 15.(3p+2q)+R(3p+2q)-R,

11.(7×+8y)(8y-7x)

12.(a+b+c)(a+b-c)
13.(x+y)-1(x+y)+1
14.(2×+y)-z)(2×+y)+
15.(3p+2q)+r(3p+2q)-r
plssss help po

 

Answer:

1. x² - 25

2. x² - 4

3. 9x² - 1

4. 4x²- 9

5. x2 - y4

6.x⁴ - 100

7. 16x²y² - 9z6