Question

please answer this please me​

Answer 1

The answer is -2.

Know that

• AB² + CA² = BC²
• AB² = 5² + (Y - 3)²
• BC² = 4² + (Y - 4)²
• CA² = 1² + 1²

Substitute into the first expression.

$5^2 + (Y - 3)^2 + 1^2 + 1^2=4^2+(Y-4)^2$

It is simplified to linear equation.

$Y^2-6Y+9+27=Y^2-8Y+32$

$2Y=-4$

∴ $Y=-2$