I need to find out the value of x in this triangle because I don’t understand the formula

x = 55 degrees

Step-by-step explanation:

Firstly, as told by the question, we know that this is an isosceles triangle because AB and BC are the same length. This means that angle A and C will be equal. Next, we also know that all angles in a triangle will always add to 180 degrees. Therefore we can write an equation adding up all the angles to solve for x:

Angle A can be represented as 'x'

Angle B is represented 'x+15'

And Angle C can also be represented 'x' as it is equal to angle A

So our formula will be in this format: A+B+C=180

x+x+(x+15)=180

To solve this equation we first take out the brackets and combine like terms:

3x+15=180

Now we need to isolate 'x' so we will end up with a numerical value for it, which we do by subtracting 15 from both sides and then dividing both sides by 3:

3x+15-15=180-15

3x=165

3x/3=165/3

This gives us:

x=55

Hope this helped!

step-by-step explanation:

de-gf

hj=3x+20

ji=15x-64