Test 7 Section 4 Question 6

Hi Mike…SAT 7, Section 4, Q6: I now see the shortcut here (that both sides of the equation are perfect squares,) but if I did expand and FOIL the left side, wouldn’t I still get the correct “a” values even though it takes longer? I can’t get it to work !! Can you please show the alternate path math steps? Or is recognizing the perfect squares the ONLY way to solve this one ? Thanks!

SAT 8, Section 3, Number 7

Hi Mike, I’m asking about SAT 8, Section 3, Number 7. Is it always best to immediately plug in answer choices on questions like this? For the algebraic practice, I rewrote the equation as a quadratic and solved for (x=5) and (x= -1). Then sub’d each value back into the given equation to find that only (x=5) worked. OK…but what a time-killer at #7 out of 20. Any other solution path to consider? Thanks!

If the sum of the first six terms of an arithmetic sequence is 78 and the sixth term is 23…

Hey Mike, Is there a way do to this sequence problem without using the
“S=n[a1 + a…]” formula?
In an arithmetic sequence, each term after the first is found by adding the same number to the preceding term. If the sum of the first six terms of an arithmetic sequence is 78 and the sixth term is 23, what is the second term?
A) 3 B) 4 C) 7 D) 10 (The correct answer is 7)

A function is defined for x and y such that f(x,y) = -2xy + y + x – 4…

Functions – – Ugh!

A function is defined for x and y such that f(x,y) = -2xy + y + x – 4. So, for x=2 and y=3, f(2,3)= -2x2x3+3+2-4 = -12+1 = -11. If x and y are to be chosen such that f(x,y) = f(y,x), then which of the following restrictions must be placed on x and y?

A) x>0 and y>0
B) x<0 and y<0
C) x = y
D) No restrictions are needed

Factoring the polynomial x^12 -9 reveals a number of factors for the expression. Which of these is NOT one of the possible factors?

Hi Mike: I get tripped up by factoring Qs like this, especially “NOT” Qs… What’s the best way to solve this? Tks!
Factoring the polynomial x^12 -9 reveals a number of factors for the expression. Which of these is NOT one of the possible factors?
A) x^6 +3
B) x^6 -3
C) x^3 + [radical 3]
D) x^3 – [radical 3]
E) x – [radical 3]

Erin and Amy are playing poker. At a certain point in the game, Erin has 3 more chips than Amy…

Hey Mike, I am pretty strong in word probs, and on this one, I keep getting an answer of 7 chips, but correct answer says 11 chips. I don’t get it !

Erin and Amy are playing poker. At a certain point in the game, Erin has 3 more chips than Amy. On the next hand, Erin wins 4 chips from Amy. Now how many more chips does Erin have than Amy?
A) -1
B) 1
C) 7
D) 11
E) 14