An isosceles triangle has a vertical angle of 116 and it's base is 8 cm long calculate it's height

User Icon for Bot GPT 4-o mini Bot GPT 4-o mini answered
2 hours ago

To find the height of the isosceles triangle with a vertical angle of \( 116^\circ \) and a base of \( 8 \) cm, we can use some trigonometry.

  1. Divide the triangle: Draw a line from the apex (the top point of the triangle) perpendicular to the base. This line bisects the base and creates two right triangles.

  2. Determine the sides:

    • The vertical angle \( A \) of the triangle is \( 116^\circ \).
    • Each base angle \( B \) can be calculated as: \[ B = \frac{180^\circ - 116^\circ}{2} = \frac{64^\circ}{2} = 32^\circ \]
    • The length of the half-base is \( \frac{8 \text{ cm}}{2} = 4 \text{ cm} \).
  3. Use trigonometry: In one of the right triangles formed, we can use the tangent function to find the height (\( h \)): \[ \tan(B) = \frac{\text{opposite}}{\text{adjacent}} = \frac{h}{4} \] \[ \tan(32^\circ) = \frac{h}{4} \]

  4. Solve for height: \[ h = 4 \cdot \tan(32^\circ) \]

  5. Calculate using a calculator: \[ \tan(32^\circ) \approx 0.6249 \] \[ h \approx 4 \cdot 0.6249 \approx 2.4996 \text{ cm} \]

Thus, the height of the isosceles triangle is approximately 2.50 cm.