Question 1169566
Yato,  2b

Brother Yukine, b


Second sentence,  {{{(2b-5)/(b-5)=b-7}}}

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{{{b^2-14b+40=0}}}
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{{{b=(14+-sqrt(36))/2}}}

{{{cross(b=(14+- 6)/2)}}}

<s>The one which works:  b=4</s>


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R E T R Y
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Returning to quadratic,
{{{b^2-14b+40=0}}}

Factorize,
{{{(b-4)(b-10)=0}}}

Possible solutions to check, b=4  or  b=10.


Using the quotient description  {{{(2b-5)/(b-5)=b-7}}}

b if 4
{{{(8-5)/(4-5)=4-7}}}
arithmetic works but either age five years ago must not be negative.

b if 10
{{{(20-5)/(10-5)=10-7}}}
{{{15/5=3}}}
{{{3=3}}}
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b=4 will not work.
b=10 will work.