Question

Tính |a²-b²| biết \(\dfrac{1}{3}\)=\(\dfrac{2a-b}{5a+b}\)và a+b=5

Answer 1

\(\dfrac{2a-b}{5a+b}=\dfrac{1}{3}\)

=>\(3\left(2a-b\right)=5a+b\)

=>6a-3b=5a+b

=>6a-5a=b+3b

=>a=4b

a+b=5

=>4b+b=5

=>5b=5

=>b=1

\(a=4\cdot1=4\)

\(\left|a^2-b^2\right|=\left|4^2-1^2\right|=15\)