Explanation for Question 7 From the Math (No Calc) Section on the 2018 April Sat
Question seven asks in triangle, 2 ABC above side AC is extended to point D what 3 is the value of Y minus X? 4 So the first thing we can do here is we can solve for X 5 and we can do that because we know that three angles in a triangle 6 are equal to 180. 7 So 1 0 5 plus 35 plus 8 X is equal to 180. 9 We can rewrite this as one 40 plus X is equal to 180. 10 And when we solve for X, we get X is equal to 40. 11 So we know that X is equal to 40 degrees. 12 Now, the second thing we know is that X plus Y is 13 equal to 180 as well. 14 And that's because X and Y are both angles on a straight line. 15 So the angle of line is always 180 degrees. 16 So we can plug in 40 for X and we 17 can find if we solve for Y that Y is equal to 18 140. And I just got that by subtracting 40 from both 19 sides. Finally, 20 the question's asking, what is Y minus X? 21 Well, why is 140 an axis 40? 22 Which means that Y minus X is equal to a hundred. 23 And the correct answer is.