so here we are told that angle CED is 39 degrees and in this diagram we have three angles the first one is Angle CED the next one is angle CEL and the last one is angle LED so angle c e l + angle LED is equals to angle c e d so in this case 3 x - 6 + x + 25 should be equal to 39 degrees collect the like terms 3 x + x + 25 - 6 is equals to 39 degrees 4X + 19 is equals to 39 cross the 19 over the equals sign that you have 4 x is equals to 39 + 19 4 x is equals to 68 divide both sides by 4 and x is equals to 17 then substitute replace where there is x with seventeen so in this case angle c e l will be 3 * 17 -6 we are multiplying 3 by 17 because it was 3 x and we got the value of x to be 17 so 3 * 17 is 51 -6 is 45 so angle CEL is 45 degrees you can do the same with the other angle that is angle LED and you get x to be 42