Question

[Lê Nguyễn Hoàng Mỹ Đình]

Cho \(\frac{x+16}{9}=\frac{y-25}{16}=\frac{z+9}{25}\) và \(2x^3-1=15\)

Tìm x,y,z.

Answer 1

[Đinh Đức Hùng]

2x³ - 1 = 15 <=> 2x³ = 16

<=> x³ = 8 = 2³

=> x = 2

\(\Leftrightarrow\frac{2+16}{9}=\frac{18}{9}=2\)

\(\Leftrightarrow\frac{y-25}{16}=2\) => y - 25 = 32 => y = 57

\(\Leftrightarrow\frac{z+9}{25}=2\) => z + 9 = 50 => z = 41

Vậy x = 2; y = 57; z = 41