GCSE Maths: Algebra: Solving linear equations given angles inside a quadrilateral

The angles of a parallelogram are given by 2x, 3x-15 and 2x+24
Using the fact that the angles add to 360 degrees, we can set up and solve an equation in terms of x
This lets us use algebra to solve the linear equations

[josepbando]

Thank you so much, I was stuck on a question like this.

[Tkt]

Thanks for the video. But when we add all the angles keeping x as 39, the sum doesn't equal to 360. Can u plz explain that