



 
Hi June, In my response to this question when Julie sent it I commented that the key is to see the pattern in the squares
The pattern to see is that, in each case if you know the coefficient of x, + 2a or 2a, take half of it and square the result you get the constant term a^{2}. In the problem you sent, on the left side you have x^{2}  6x. If you want to expand this to form a square you need to take the coefficient of x, which is 6, divide by 2 to get 6/2 = 3 and then square this number. The square of 3 is 9 so to make x^{2}  6x into a square you need to add 9 since x^{2}  6x + 9 = (x  3)^{2}. This is all preliminary work to writing my solution to the problem. The preliminary work was to determine that I need to add 9. here then is how I start my solution
add 9 to each side to get
Can you complete the problem now? You sent us two other problems that you can solve similarly. In the second problem you sent , 2x^{2}  3x + 1 = 0, there is an extra step. You need the coefficient of x^{2} to be 1 so divide both sides of the equation by 2 to get
and apply the technique above to this expression. Penny  


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