Isosceles triangle 8

If the rate of the sides an isosceles triangle is 7:6:7, find the base angle correct to the nearest degree.

Correct answer:

B =  65 °

Step-by-step explanation:

$$\begin{gathered} a=7 \\ b=6 \\ \cos B=b\mathrm{/}2:a \\ B={\displaystyle \frac{180\mathrm{°}}{\pi }}\cdot \arccos ({\displaystyle \frac{b\mathrm{/}2}{a}})={\displaystyle \frac{180\mathrm{°}}{\pi }}\cdot \arccos ({\displaystyle \frac{6\mathrm{/}2}{7}})=65\text{°}=64\mathrm{°}37^{\mathrm{\prime }}23\mathrm{"} \end{gathered}$$

Try calculation via our triangle calculator.

Try another example

Related math problems and questions:

• Ratio iso triangle
  The ratio of the sides of an isosceles triangle is 7:6:7 Find the base angle to the nearest answer correct to 3 significant figure.
• Roof angle
  The roof of the house has the shape of an isosceles triangle with arms 4 m long and the size of the base 6 m. How big an angle alpha does its roof make?
• Flowerbed
  The flowerbed has the shape of an obtuse isosceles triangle. Arm has a size 5.5 meters, and an angle opposite to the base size is 94°. What is the distance from the base to the opposite vertex?
• Isosceles triangle 10
  In an isosceles triangle, the equal sides are 2/3 of the length of the base. Determine the measure of the base angles.
• IS triangle
  Calculate interior angles of the isosceles triangle with base 40 cm and legs 22 cm long.
• Isosceles triangle
  What are the angles of an isosceles triangle ABC if its base is long a=5 m and has an arm b=4 m.
• Trigonometry
  If you know that cos(γ) = sin (806°), what is the angle γ?
• Isosceles triangle
  Calculate the size of the interior angles and the length of the base of the isosceles triangle if the length of the arm is 17 cm and the height to the base is 12 cm.
• SAS triangle
  The triangle has two sides long 7 and 19 and included angle 36°. Calculate area of this triangle.
• Right triangle trigonometrics
  Calculate the size of the remaining sides and angles of a right triangle ABC if it is given: b = 10 cm; c = 20 cm; angle alpha = 60° and the angle beta = 30° (use the Pythagorean theorem and functions sine, cosine, tangent, cotangent)
• Triangle TBC
  TBC is isosceles triangle with base TB with base angle 63° and legs length |TC| = |BC| = 25. How long is the base TB?
• Find the area
  Find the area of the triangle with the given measurements. Round the solution to the nearest hundredth if necessary. A = 50°, b = 30 ft, c = 14 ft
• Right triangle
  A right triangle ABC is given, c is a hypotenuse. Find the length of the sides a, b, the angle beta if c = 5 and angle alfa = A = 35 degrees.
• Trapezoid MO
  The rectangular trapezoid ABCD with the right angle at point B, |AC| = 12, |CD| = 8, diagonals are perpendicular to each other. Calculate the perimeter and area of ​​the trapezoid.
• Right triangle
  Calculate the missing side b and interior angles, perimeter, and area of ​​a right triangle if a=10 cm and hypotenuse c = 16 cm.
• Right triangle
  Calculate the length of the remaining two sides and the angles in the rectangular triangle ABC if a = 10 cm, angle alpha = 18°40'.
• The aspect ratio
  The aspect ratio of the rectangular triangle is 13: 12: 5. Calculate the internal angles of the triangle.