So the angles in this are alternate interior angles. All alternate interior angle are congruent, so to find x, you make the equation equal 85. So it would be 14x+1=85. Next you isolate the variable by subtracting the 1 to the other side then dividing the entire expression by 14. In the end you should find that x=6. I assume that substituting it back in is substituting the x back into the expression. So just replace x with 6. 14(6)+1=85; 84+1=85; 85=85.
The answer is x=6, they are alternate interior angles, and substituting the new x into the expression should result in 14(6)+1=85; 84+1=85; 85=85.
