7x^2-x-8=0 решить уравнение)

Question

7x^2-x-8=0 решить уравнение)

Answer 1

7х^2 – х – 8 = 0

7х^2 + 7х – 8х – 8 = 0

7х(х + 1) – 8(х + 1) = 0

(х + 1)(7х – 8) = 0

х + 1 = 0

7х – 8 = 0

х = – 1

х = 8/7 = 1 1/7