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Rove the sum of two rational numbers is rational where a, b, c, and d are integers and b and d cannot be zero.

Steps Reasons
1. a over b plus c over d Given
2. Multiply to get a common denominator
3. ad plus cb all over bd Simplify


Fill in the missing step in the proof.

1 Answer

3 votes

Answer:


(ad+bc)/(bd)

Explanation:


Greetings!


I'm~Isabelle~Williams~and~I~will~be~answering~your~question!


Let,(a)/(b) ~and ~(c)/(d)~be~two~rational~numbers, ~where~ b ~and~ d ~are~ not~ zero ~and~ a, ~b, ~c ~and \\~d ~are~ integers.


1.~Given:


(a)/(b) +(c)/(d)


2.~Now,~we~multiply~to~get~a~common~denominator:


(a)/(b)+(c)/(d)=(ad)/(bd)+(cb)/(db)


3.~Then~simplify:


(a)/(b)+(c)/(d)=(ad)/(bd)+(cb)/(db)=(ad+bc)/(bd)


4.~Since,b\\eq 0,~d\\eq 0,~then,~bd,~ad,~bc~and~ad+bc~are~integers~too.~So~the\\ fraction~will~be:


(ad+bc)/(bd)


Thus,~making~it~a~rational~number!


Hope~this~answer~helps!~and~have~an~amazing~day~ahead!


-Isabelle~Williams

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