Question

3 х в квадрате -7х-6=0

Answer 1

3x² - 7x - 6 = 0
D = b² - 4ac
D = ( - 7)² - 4 × 3 × ( - 6) = 49 + 72 = 121 = 11²
x₁ = 7 + 11/ 2 × 3 = 18/ 6 = 3
x₂ = 7 - 11/ 2 × 3 = - 4/ 6 = - 2/3

Ответ: x₁ = 3, x₂ = - 2/3

Answer 2

$3x^2-7x-6=0 \\ \Delta=b^2-4ac=(-7)^2-4*3*(-6)=49+72=121=11^2 \\ \sqrt{\Delta}= \sqrt{11^2}=11 \\ x_1= \frac{-b- \sqrt{\Delta} }{2a}= \frac{7-11}{6}= \frac{-4}{6}=- \frac{2}{3} \\ x_2= \frac{-b+ \sqrt{\Delta} }{2a}= \frac{7+11}{6}= \frac{18}{6}=3$