Lets figure out the third angle (y) in the triangle first.
70 + 64 + y = 180
134 + y = 180
y = 46
We now know that 46 is our third angle. Therefore, we can subtract 46 (y) from 180 (the total between x and the third angle) to get our final answer. 134 Degrees.
for these kinds of problems the outside angle always equals the opposite 2. meaning angle x=64+70 which is 134 degrees. you can double check this because all triangles equal 180 degrees. meaning that the last angle in the triangle is 46. 46+70+64=180.
