Question

Fie a/b=2/3.Sa se afle valoare expresiei a+5b/2a-b........raspunsul e 17?

Answer 1

2b=3a⇒b=3a/2;
⇒a+5b/2a-b
⇒a+5·3a/2/2a-3a/2
⇒a+15a/2/4a/2-3a/2
⇒2a/2+15a/2/a/2
⇒17a/2/a/2
⇒17a/2·1/a/2
⇒se reduce a/2 cu a/2;
⇒17/1=17;