The line should equal 180 degrees, so we would subtract 122 from 180 to get 58 degrees. Since the triangle is equilateral, each angle is the same measure, so I believe m<1 should be 58 degrees.
Four and ninety four thousandths. You're welcome!
Since these are supplementary angles (two angles which sum to 180°) we can say:
4x+x=180 combine like terms on left side
5x=180 divide both sides by 5
x=36°
