Răspuns :
{a+b=680 {a+b=680 inmultim cu -95
{115a/100+95b/100=710⇒ {115a+95b=71000 ⇒
{-95a-95b=-64600
{115a+95b=71000 se reduce b⇒
115a-95a=71000-64600
20a=6400
a=6400/20=320
b=680-320
b=360
{115a/100+95b/100=710⇒ {115a+95b=71000 ⇒
{-95a-95b=-64600
{115a+95b=71000 se reduce b⇒
115a-95a=71000-64600
20a=6400
a=6400/20=320
b=680-320
b=360
{a+b=680 <=> {a+b=680 inmultim cu -95 <=>
{115a/100+95b/100=710 <=> {115a+95b=71000 <=>
<=>{-95a-95b=-64600
<=>{115a+95b=71000
Le adunam, iar b-ul se va reduce , ramanand o ecuatie simpla , cu o singura necunoscuta a
=>115a-95a=71000-64600=>20a=6400=>=>a=[tex] \frac{6400}{20} [/tex]=320=>a=320
a+b=680 , a=320=> b=680-320=>b=360
{115a/100+95b/100=710 <=> {115a+95b=71000 <=>
<=>{-95a-95b=-64600
<=>{115a+95b=71000
Le adunam, iar b-ul se va reduce , ramanand o ecuatie simpla , cu o singura necunoscuta a
=>115a-95a=71000-64600=>20a=6400=>=>a=[tex] \frac{6400}{20} [/tex]=320=>a=320
a+b=680 , a=320=> b=680-320=>b=360