Question

(2x-1)²-(x-3)²=x(2x-1)-10

Answer 1

Răspuns:

In pozele atașate

Coroana??

Answer 2

2x² - 2 * 2x * 1 + 1² - x² + 2 * x * 3 - 3² = 2x² - x - 10

4x² - 4x + 1 - x² + 6x - 9 = 4x² - x - 10

4x² - x² - 4x² - 4x + 6x + x = 1 - 9 + 10

3x² - 4x² + 2x + x = - 8 + 10

- x² + 3x = 2

- x² + 3x - 2 = 0

a = - 1

b = 3

c = - 2

Delta = b² - 4ac

D = 3² - 4 * ( - 1 ) * ( - 2 )

D = 9 + 4 * ( - 2 )

D = 9 - 8

D = 1

X1 = ( - b - rad. delta ) / 2a

X1 = - 3 - 1 / 2 * ( - 1 )

X1 = - 4 / - 2

X1 = 2

X2 = ( - b + rad. delta ) / 2a

X2 = - 3 + 1 / 2 * ( - 1 )

X2 = - 2 / - 2

X2 = 1