In order to determine whether the equations are parallel, perpendicular, or neither, let's simply each equation into a slope-intercept form or basically, solve for y.
Let's start with the first equation.

Cross multiply both sides of the equation.


Subtract 6x on both sides of the equation.


Divide both sides of the equation by -5.


Therefore, the slope of the first equation is 4/5.
Let's now simplify the second equation.

Add x on both sides of the equation.


Divide both sides of the equation by -4.


Therefore, the slope of the second equation is -5/4.
Since the slope of each equation is the negative reciprocal of each other, then the graph of the two equations is perpendicular to each other.
If the ratio is 90:3 and there are 4 groups of 3 in 12, then the ratio would then be 450:12, leaving you with 450 as the answer. Hope I helped
In which step did the student first make an error?
Answer: Step 2
Step 2 should be:
−3y = -45 + 6z
Answer:
See below.
Step-by-step explanation:

Answer:
192.1%
Step-by-step explanation:
The formula for the amount of interest is ...
i = Prt . . . . . where i is the interest amount, P is the principal, r is the annual rate, and t is the number of years. (Here, we have a fraction of a year.)
Solving for the rate, we have ...
r = i/(Pt)
For "exact" interest, we use 365 days in the year. So, for a time of 19 days of 365, the interest rate is ...
r = $35/($350·19/365) ≈ 1.921 = 192.1%