[Video] Q4: In the figure above, rt = tu. what is the value of x ?

Explanation for Question 4 From the Math (No Calc) Section on the Official Sat Practice Test 8

All right. So working with question number four, we see that we've got a 2 couple of triangles and they're laying over each other, 3 which creates some overlap. And we're trying to find this angle here, 4 angle X, and what might be difficult about this question is knowing where to 5 get started. Right? And so we want to start with the information that they 6 give us and they tell us that RT is equal to T U. 7 So what that means is that this line here is congruent to this 8 line. Here. We can ask ourselves, 9 what do we know about having equal side blanks? 10 And one thing that we should know is that if the side lengths are 11 equal, then they're corresponding angles are also going to be equal. 12 So angle R is equal to angle you. 13 And if angle R is equal to angle you, we can call them Y 14 angle Y. So that means that Y plus Y plus 114 15 should be equal to 180, right? Because one 14 is here and then two 16 Ys, they make up one triangle. And the angles inside of a triangle need 17 to add up to 180. So I can do 180 minus 114. 18 That gives us oops. Oh yeah. 19 That gives us 66. So two Ys equal to 66. 20 So that means that Y is equal to 33 degrees, 21 right? So these two angles here are both 33 22 degrees. So now we have to decide which, 23 which triangle do we want to use? Do we want to use this little 24 triangle to find X, or do we want to use this big triangle to 25 find X? And the answer is we want to use the big triangle to 26 find X because it's going to be really diffi...