Answer:

Step-by-step explanation:
This is the answer because it is subtracted so that you get the answer
Answer:
You can see the graph below.
To answer the question, you need to draw a vertical line from x = 12h up, until the line meets with the line.
Once the line meets with the line, draw a horizontal line from that point, and the value where this line intersects with the y-axis will be the distance from home after 12 hours.
The graph is kinda hard to read because the line is really steep, the green line is the equation y = 40*x
the red line is a line at x = 12
The black dashed line is the horizontal line that intersects with the y-axis.
In the graph, you can see that the dashed line intersects the y-axis at around y = 475.
Then a good estimate is that the distance after 12 hours is 475 (miles).
Now, we can compare this with the direct calculation, just replace x by 12 in the given line:
y = 40*12 = 480.
So our estimation is really accurate.
x = Nick's age y = Sara's age
Nick is 8 years older than Sara, therefore
y = x - 8
Answer: 160 liters of the
40% solution and 80 liters of the 70% solution will be used.
Step-by-step explanation:
Let x represent the number of liters of 40% antifreeze solution that should be used.
Let y represent the number of liters of 70% antifreeze solution that should be used.
The volume of the mixture to be mixed is 240 liters. It means that
x + y = 240
The 40% antifreeze solution is to be mixed with a 70% antifreeze
solution to get 240 liters of a 50% solution. This means that
0.4x + 0.7y = 0.5(240)
0.4x + 0.7y = 120 - - - - - - - - - - - -1
Substituting x = 240 - y into equation 1, it becomes
0.4(240 - y) + 0.7y = 120
96 - 0.4y + 0.7y = 120
- 0.4y + 0.7y = 120 - 96
0.3y = 24
y = 24/0.3
y = 80
x = 240 - y = 240 - 80
x = 160
1/2 by 3 equal 5 /1 so yea it’s easy that’s rights