We know that the total angle measure in a triangle is always 180°, so first we need to find the angle value of BAC. They give us a straight line aligning with this angle and measure of 98° for the angle DAB (which is forming other part of line) and a line is 180° so we subtract and find that angle BAC is 82°.
Now that we know the angle measure of 2 angles in the triangle, we add them up and get 114°. Now we subtract this from 180° and get 66°, which is the measure of x.
