Math, asked by saikrishnan, 1 year ago

find 2 numbers such that the sum is 18 and sum of their squares is 290

Answers

Answered by william
1
a + b = 18 .......................................................(1)
a^2 + b ^2 = 290 ...............................................(2)
we will use the algebraic identity formula 
(a + b) ^2 = a ^2 + b^2 + 2ab.............................(3)
18^2 = 290 = 2ab
324 - 290 = 2ab
34 = 2ab
ab = 34 /2 
ab = 17,..............................................................(4) 
a = 17 / b............................................................ (5 ) 
apply (5) in (1) we get,
a + b = 18 
17/ b + b = 18
17+ b^2 = 18b
b^2 - 18b + 17
(b - 17) (b -1)
b = 17,1 ..............................................................(6)
if b= 17 apply in 5 we get 
a = 17/17
a = 1
if b= 1
then a = 17,
(a,b) = ( 17,1) or ( a,b) = (1,17)


anshashwin25: 17+1=18,17^2+1^2=290 plz pick it as the best
Anonymous: wow dont u think our answers are somelike same
william: most welcome
anshashwin25: ya i think but i had given the easier way to calculate this answer @Bpjindia0720
Answered by Anonymous
2
a + b = 18 
a^2 + b ^2 = 290 
(a + b) ^2 = a ^2 + b^2 + 2ab
18^2 = 290 = 2ab
324 - 290 = 2ab     34 = 2ab
ab = 34 /2 =17

a = 17 / b
when we put 5 in 1 
a + b = 18 
17/ b + b = 18
17+ b^2 = 18b
b^2 - 18b + 17
(b - 17) (b -1)
b = 17,1
if b= 17 applied in 5 comes 1
a = 17/17
a = 1
 b= 1
 a = 17,
b=1

anshashwin25: 17+1=18,1762+1^2=290
william: same thinking
Anonymous: oh yes might be
Anonymous: u know that when the concept is same mostly the outcome is same
Anonymous: am i right
william: yep yep
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