Can you solve this quadratic equation?

Date: 7r^2 - 14r =  -7  first we add to both sides of the equation number (+7) and we get => 7r^2 -14r +7 = 0 now we divide both sides with number (7) and we get  r^2 -2r + 1 = 0  => this is the square of the binomial => (r - 1)^2 = 0
=>  r - 1 = 0  when we add to both sides number (+1) we get final solution
=> r=1 This is only one solution of this quadratic equation. 

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