Question

simplifique as expressões


a)7x²+2(x²-1)

Answer 1

7x² + 2(x²-1) 

7x² + 2x² - 2 

9x² - 2                            ok

Answer 2

7x² + 2(x²-1)
7x² + 2x²-2
9x²-2 = 0

9x² = 2
x² = 2/9
x = +-$\sqrt{2/9}$