Question

Need help with understanding these problems and the right approach.

Question 1. If (p)(q^3)(t^4) > 0, which of the following products must be positive?
(F) pq
(G) pt
(H) qt
(J) pqt
(K) (p)(q^2)

Question 2. For real numbers x and y, when is the equation |2x + 3y| = |2x - 3y| true?
A) Never
B) Always
C) Only when 2x = 3y
D) Only when x = 0 and y = 0
E) Only when x = 0 or y = 0

Question 3. For all real numbers x and y such that the product of y and 4 is x, which of the following expressions represents the sum of y and 4 in terms of x?
A) x + 4
B) 4x + 4
C) 4(x+4)
D) (x+4)/4
E) (x+16)/4

Answer 1

question 1

one approach
consider the situation when the values are positive and when negative
t^4 will always be positive t can be positive or negative
when q is negative q^3 is negative
p can be positive or negative