Question

Va rog!!!!<br /><br />
a+b=25<br />
ab=144<br /><br />
a=? ; b=? Dau coroană
+ trei de multumesc

Answer 1

a+b=25
a*b=144
⇒a=144/b
144/b +b =25
144+b²=25b
⇔b²-25b+144=0
Δ=625-576
Δ=49
x₁=16
x₂=9

⇒⇒⇒ a₁=144/b₁
⇒⇒⇒a₁=144/16
a₁=9

a₂=144/b₂
a₂=144/9
a₂=16

⇒⇒⇒⇒ a∈{9;16}
⇒⇒⇒⇒ b∈{16,9}