Question

Решите функцию
7х2-5х=у
7х-5=у

Answer 1

7х^2 - 5х = у

 7х - 5 = у

Решение

7х^2 - 5х = y

7х - 5=y

7х^2 - 5х - 7х + 5 = 0

7х^2 - 12х + 5 = 0

D = 144 - 140 = 4 = 2^2

X1 = ( 12 + 2 ) : 14 = 1

X2 = ( 12 - 2 ) : 14 = 10/14 = 5/7

y = 7x - 5

y1 = 7 - 5 = 2

y2 = 7•( 5/7 ) - 5 = 5 - 5 = 0

Ответ ( 1 ; 2 ) ; ( 5/7 ; 0 )