Question

Find the value of x in the isosceles or equilateral triangles.

Answer 1

86°

Step-by-step explanation:

Since this is an isosceles triangle, two of the sides and angles are the same. If the edge angles are both the same, 47°, then we can use the equation 47°+47°+x=180° to find the missing angle. 47°+47° is 94°. If 94° + x = 180°, then we can subtract 94° from 180° to get the missing angle. The value of the missing angle is 86°.

Answer 2

x = 86°

Step-by-step explanation:

Let the Δ be ΔABC

∠ABC = 47° (Since this is an isosceles triangle, there are two equal sides and two equal angles).

∴ The angle formed at <BAC = 47° too (The 2 equal angles are 47°)

The only remaining angle is the one at x, which is

By angle sum property, 47° + 47° + x = 180°

94° + x = 180°

x = 86°