Question

10. If a2-4a + b2 - 2b + 5 = 0, find the value of a + b.
please do not write random things just for points.​

Answer 1

Answer:

The answer is 3

Step-by-step explanation:

Given  $a^2-4a+b^2-2b+5=0$

          $\Rightarrow (a^2-4a+4)+(b^2-2b+1)=0\\\Rightarrow (a-2)^2+(b-1)^2=0$

But we know that $(a-2)^2\ge 0$ and $(b-1)^2\ge 0$

and since their sum is zero $\Rightarrow (a-2)^2=0$ and $(b-1)^2=0$

                                             $\Rightarrow a-2=0$ and $b-1=0$

                                             $\Rightarrow a=2,b=1$

Hence $a+b=2+1=3$