Question

(2y-3)(y+1)+y(y-2)=3(y+2)^2

Answer 1

(2y - 3)(y + 1) + y(y - 2) = 3(y + 2)²

⇔ 2y² + 2y - 3y - 3 + y² - 2y = 3(y² + 4y + 4)

⇔ 3y² - 3y - 3 = 3y² + 12y + 12

⇔ 3y² -3y - 3y² -12y = 12 + 3

⇔ -15y = 15

⇔ y = -1

Vậy S = {-1}

Answer 2

Đề yc làm gì em?

Answer 3

\(\left(2y-3\right).\left(y+1\right)+y.\left(y+2\right)=3\left(y+2\right)^2\\ \Leftrightarrow2y^2-y-3+y^2+2y=3y^2+12y+12\\ \Leftrightarrow3y^2-2y^2-y^2+12y-2y+y=-3-12\\ \Leftrightarrow11y=-15\\ \Leftrightarrow y=-\dfrac{15}{11}\\ Vậy:S=\left\{-\dfrac{15}{11}\right\}\)