Which of the following equations have only one solution? Select all correct answers. x²-x-6=0
5 x2 + 20 x+ 20 = 0
9x2 - 25 = 0
4x2+4 x=0
12+ 6 x+9= 0​

The equations which have only one solution is: 5x²+20x+20=0,

Step-by-step explanation:

5x^2 + 20x + 20 = 0

12+ 6x +9= 0​

Step-by-step explanation:

5x^2 + 20x + 20 = 0  /5             12 + 6x + 9 = 0        

x^2 + 4x + 4 = 0                          6x = -9-12

(x+2)^2=0                                    6x = -21

x + 2 = 0                                      x = -21/6

x=-2                                             x = -3.5

goog may have it for you

not only in mathematics, scientific proof also are required in the other field of science. also maths proofs are of particular structure, containing steps and logics. so proving is like doing science, it is science. that's why it is important to prove. 

an inaccurate proof leads to errors, or stating results that are not accurate.  which wil mess the probelm up you dont want this