Firstly, let's set up our equation. Place the two coordinates in the slope formula and have it equal 8:
Next, combine like terms:
Next, multiply both sides by 7:
Next, add 4 onto both sides of the equation:
Lastly, divide both sides by 2 and <u>your answer will be </u>
We are given that there are a total of 78 students. If we set the following variables:
Then, the sum of all of these must be 78, that is:
Since there are 15 in chemistry and physics and 47 in chemistry, we may replace that into the equation and we get:
Simplifying:
Now we solve for P by subtracting 62 on both sides:
Therefore, there are 16 students in physics