Find the measurements of the angles if a triangle if the measure of one angle is twice the measure of a second angle and the third angle measurer 4 times the second angle decreased by 58

Set x = the first angle, then construct equations for the 2nd and 3rd angles from the facts you have been given. Then set up an equation of the sum of the three angles, which you should recall must equal 180 degrees. Now you have a single equation that can be solved for x. Hope this helps.