Answer:
Let x = # of commercials
y = # of movies
<u>System of Equations:</u>
x + y = 90
40x + 110y = 500
Step-by-step explanation:
We have to set our variables before we start solving. After setting the variables, we can set up the equations. If x = # of commercials and y = # of movies, then we can assume x + y = 90, as there have been a total of 90 commercials and movies played altogether. Then, we know that their worth is $500, so the price of all the commercials played and the price of all the movies played (which is 40x + 110y) sum to $500.
Simplify both to 1/2 because both numerators are half of their denominators. Then multiply straight across to 1/4.
Roots of the equation 3x² -3x-6=0 are -1 and 2,
all choices are given wrong
3*2²-3*2-6=0
12-6-6=0
0=0, which is true , so root is 2
3*20²-3*20-6=0
600-60-6=0
534=0 which is wrong, so root is 2, but not 20
<u>Direct Variation:</u> 
when y = 7: 
14 = 15x
<u>Inverse variation:</u> y*x = k
15 * 2 = k
30 = k
when y = 7: 7 * x = 30
I don't know what the relation in your problem is, but I'll just explain this using my own example.
Let's use the following relation as the example (pretend it's a table of values):
x | y
0 | 1
2 | 4
4 | 7
6 | 10
To write the relation as ordered pairs, you need the x and y values from the table. An ordered pair is written like this: (x,y).
Based off of this explanation, the ordered pairs from this example would be:
(0,1) (2,4) (4,7) (6,10)
