After being rearranged and simplified, which of the following equations could be solved using the quadratic formula? Check all that apply. a) -3x^2+9x+3x^2=14+x-1 b)5x+4=3x^-2 c)-x^2+4x+7=2x^2-9 x^3+x^2+x=0

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Answer:


Step-by-step explanation:

a) cannot -3x^2 and 3x^2 cancel out. What is left is a linear equation.

9x = 14 +x - 1

b) cannot use the quadratic formula to solve this equation the x on the right must be made positive. When it is, it is in the denominator as in [tex]\frac{3}{x^2}[/tex]When that happens, there is no way to get the 5x to remain as it is. One way or another you will wind up with 5x^3 + 4x^2 = 3 which is a cubic, and not a quadratic.

c) If c ends where I think it does, the quadratic will work on it.

-x^2 + 4x + 7 = 2x^2 - 9

0 = 2x^2 + x^2 - 4x - 7 - 9

0 = 3x^2 - 4x - 16

a = 3 ; b = - 4 and c = - 16

The solutions are (3.07,0) and (-1.74,0) both are rounded.

d)x^3 + x^2 + x = 0 could have the quadratic used on it.  a = 1, b=1, c = 1 which a common factor of x is taken out by the distributive property.

x(x^2 + x  + 1) = 0 I think the letter d for the question number has been omitted. The solution sets are (0,0) and 2 complex roots. But that was not what you were asking. You were just asking if you could use the formula and you can if I've separated out things correctly. If I have not then c cannot be solved with the quadratic.


Answer:

it's C and B, it is atleast

Step-by-step explanation:

as of March 2021