trinomial

 

Find the values of $a$ such that $ax^2+15x+4-12x+5$ is the square of a binomial.    

 

 

                                              ax^2+15x+4-12x+5    

 

Combine like terms                ax² + 3x + 9    

 

For this to be a square    

then b² – 4ac must = 0          3² – (4)(a)(9)  =  0    

 

                                                        9 – 36a  =  0           

 

                                                              36a  =  9    

 

                                                                   a  =  0.25    

 

The problem doesn't ask for      

the binomial, but it's (0.5x + 3)    

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