Quadratic equation and a lsolve function

[ValeryOchkov]

There is a quadratic algebraic equation. Is it possible, according to its coefficients a, b, and c, to form a system of two linear algebraic equations with the same roots as the quadratic equation?

Others word! Can I use the lsolve function for the solving a quadratic algebraic equation?

[Fred_Kohlhepp]

I used to work with older (back then) engineers who were adept at EXCEL and adverse to Mathcad,  We could get curve fits to polynomials by "creating" a column with the values for the other powers and using the EXCEL function "linest".  A similar trick should work for lsolve; that trick used in a least square matrix solver in Prime 4 is attached.

[LucMeekes]

Nice exercise Fred, but I don't see it solve the quadratic, or am I missing something?

Luc

[LucMeekes]

I'm afraid not, Valery:

Success!
Luc

[ValeryOchkov]

I use the lsolve function for the solving a quadratic algebraic equation?

Yes, we can!

[Werner_E · Accepted solution]

Equally unfair but a little bit nicer

[IhorHuzar]

Здравствуйте. Решал задачу в mathCad: методом наименьших квадратов рассчитать коэффициенты уравнения по результатам решения показаного в таблице полного двохуровневого трьохфакторного плана ПФЕ. Праподаватель сказал что есть ошибки, больше ничего не сказал, поможете?

[ValeryOchkov]

I think it will be better to write your question in English and put it here as new message!

And better to have comments in your Mathcad-sheet in English!