Q1
I like to use the standard form to write the equation of a perpendicular line, especially when the original equation is in that form. The perpendicular line will have the x- and y-coefficients swapped and one negated (remember this for Question 3). Thus, it will be
... 5x - 2y = 5(6) - 2(16) = -2
Solving for y (to get slope-intercept form), we find
... y = (5/2)x + 1 . . . . . matches selection C
Q2
The given equation has slope -3/6 = -1/2, so that will be the slope of the parallel line. (matches selection A)
Q3
See Q1 for an explanation. The appropriate choice is ...
... B. 4x - 3y = 5
Q4
The given line has slope -2, so you can eliminate all choices except ...
... D. -2x
Q5
The two lines have the same slope (3), but different intercepts, so they are ...
... A. parallel
I would say that the "n"th term of the sequence is 41, as the pattern increases by 10 every term.
2. They are both straight lines. The solution of a linear system is where the two lines intersect, and if they're both straight lines, then they can only cross once.
See the picture attached.