Question

Find the value of x (PLEASE HELP THIS IS a 40 point question)

Answer 1

x=40°

Explanation:

We have an isosceles triangle RST where the sides RS and ST are congruent, i.e. they have the same length.

One property of isosceles triangles is that the congruent sides form congruent angles with the other side. In other words, the measures of angles R and T are equal.

The sum of the measures of angles R, S, and T is 180°:

`m\angle R+m\angle S+m\angle T =180^\circ`

Since
`m\angle R=2x-10` ,
`m\angle T=m\angle R` and
`m\angle S=x`:

2x-10+x+2x-10 =180

Simplifying:

5x=180+20

Solving:

x=200/5

x=40°