<em>CB </em>is equal to <em>EZ </em>and <em>E </em>equals 35, and <em>E </em>and <em>C </em>are the same, therefore, both <em>E </em>equals 35. Since there's 180 degrees in a triangle, and <em>ABY </em>equals 105, you have to subtract 180 - 105 to get the other angle. When you do that, you get that <em>B </em>equals 75. You have to add <em>E </em>and <em>B</em> (35 + 75), since that's in the same triangle as <em>A. </em>When you do that, you get 110. Subtract 180 - 110 to get <em>A, </em>which is 70.
