Квадратное уравнение имеет вид $$ax^2 + bx + c = 0$$, где a, b, и c – коэффициенты.
- a) $$5x^2 - 9x + 4 = 0$$: $$a = 5$$, $$b = -9$$, $$c = 4$$.
- б) $$x^2 + 3x - 10 = 0$$: $$a = 1$$, $$b = 3$$, $$c = -10$$.
- в) $$-x^2 - 8x + 1 = 0$$: $$a = -1$$, $$b = -8$$, $$c = 1$$.
- г) $$x^2 + 5x = 0$$: $$a = 1$$, $$b = 5$$, $$c = 0$$.
- д) $$6x^2 - 30 = 0$$: $$a = 6$$, $$b = 0$$, $$c = -30$$.
- е) $$9x^2 = 0$$: $$a = 9$$, $$b = 0$$, $$c = 0$$.
Ответ: a) a = 5, b = -9, c = 4; б) a = 1, b = 3, c = -10; в) a = -1, b = -8, c = 1; г) a = 1, b = 5, c = 0; д) a = 6, b = 0, c = -30; e) a = 9, b = 0, c = 0.