Normally I have seen questions such as
Find the angles of Triangle with Ratios 2:3:7. The best method to solve this would be to solve for x using the equation 2x+3x+7x=180
Recently I have solved many questions involving ratios and I have seen that in case we know the overall sum of the ratios involved as above (Sum of angles of triangle is 180) we simply need to sum those ratios up so that they equal to a given value. What I don't understand is how has the above equation (2x+3x+7x = 180) has been constructed why did we simply add an x after each ratio ?