Explanation for Question 13 From the Math (No Calc) Section on the Official Sat Practice Test 1
So question number three is asking us for X is greater than three. 2 We'll worry about that piece later. What is equivalent to that fraction there? 3 And so what they're really asking us to do is simplify that fraction. 4 So we zoom in on this. We'll see that it's pretty complicated seeming, 5 right? Cause we have a one in the denominator and the numerator, 6 but the best first step is just going to be to focus on simplifying 7 the denominator, right? 8 Because the denominator wants me to add two fractions together. 9 But if we notice something about these two fractions, 10 we'll see that they have dissimilar denominators, 11 right? They don't have the same denominator in order to have fractions. 12 I need them to have the same denominator. So step one will be to 13 give them a common denominator. And I do that by multiplying by the denominator 14 of the opposite fraction. 15 So on this one, I'll multiply both by X plus three because that's the 16 denominator of my opposite fraction. And then on this other fraction, 17 I'll multiply by X plus two because that's the denominator on my other fraction. 18 Now we can rewrite this and we'll see X plus three, 19 all over X plus two times X plus three is equal to X 20 or not as equal to rather we're adding them together. 21 So plus X plus two shows my numerator. 22 They're all over X plus three times X plus two. 23 So now we're good to go. Our two fractions have the same denominator, 24 right? You can see I've written them perhaps ba...