Question 1207283
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if A=(4,-5) and B=(7,-9), what is the length of AB ?
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<pre>
Apply the distance formula


    d = {{{sqrt((x[2]-x[1])^2 + (y[2]-y[1])^2)}}}.


where A = ({{{x[1]}}},{{{y[1]}}}), B = ({{{x[2]}}},{{{y[2]}}}).

In your case  A = ({{{x[1]}}},{{{y[1]}}}) = (4,-5),  B = ({{{x[2]}}},{{{y[2]}}}) = (7,-9).


THEREFORE,

|AB| = {{{sqrt((7-4)^2+(-9-(-5))^2)}}} = {{{sqrt(3^2+(-4)^2)}}} = {{{sqrt(25)}}} = 5.    <U>ANSWER</U>
</pre>

Solved.