Question

Please explain how you know

Answer 1

The value of x is -10. So, the correct option is B.

The triangle shows that all the sides are equal. In geometry, a triangle with all sides equal in length is called an equilateral triangle. The triangle is hence an equilateral triangle. So all the angles in this triangle are equal.

The sum of the triangles is
`180\textdegree`. So, to find the value of x:

x+70=60

x=60-70

x=-10

Therefore, the value of x is -10. So, the correct option is B.