Answer Choices
−5
−2
1
7
Explanation for Question 2 From the Math (No Calc) Section on the Official Sat Practice Test 4
Now question number two gives us a function F of X, 2 and then it tells us that B is a constant. 3 And so you'll see the sat, throw this word around a lot. 4 Constant. That basically means that B is just the normal number and 5 B is always the same number, no matter what. 6 So for example, if B was one, it would always be one, 7 no matter what X value you plugged in. 8 And so we're given what F of X is equal to number told us 9 all for F of negative two. And so if you say, 10 okay, well, if I look at F of negative two, 11 that now means that X is equal to negative two, 12 so I'll plug in negative two for all my exes. 13 And the first problem that you run into is you can't solve because you 14 need to know what B is. And that's why they've given us this F 15 of six, uh, information, because now I know that F of six, 16 I know that's equal to seven. 17 And I also know that X is equal to six, but instead of writing 18 F of six here, I can now write seven because I actually know what 19 that value is. This is going to allow me to solve for 20 B in this equation right here. 21 Right? So three over two times six, 22 um, that is going to give us nine. 23 Plus B is equal to seven. 24 The solve for BL subtract nine from both sides. 25 And I get the two is equal to B. So now when I go 26 back up to this equation, instead of plus plus B, 27 I'll write plus two. So let me move this out of the way. 28 All right. So three over two, 29 that's going to give us negative three plus two, 30 or rather it should be negative two. That's my bad seven minus nine. 31 That's negative two. So we have negative three plus negative two that gives us 32 negative five as F of negative two. 33 And so just to summarize what we did was we solve for B using 34 this information right here. And once we had B, 35 we simply plugged it into this expression that they gave us for F of 36 X and solved for F of negative two.