Answer:
The equation of the line is y = -3/7x - 23/7
Step-by-step explanation:
To start we need to find the slope of the original line. We can do this by solving the equation for y.
3x + 7y = 21
7y = -3x + 21
y = -3/7x + 3
Now we know the slope to be -3/7. Since parallel lines have same slopes, we know the new line also will have a -3/7 slope. We can now use that along with the given point in point-slope form to find the equation.
y - y1 = m(x - x1)
y + 5 = -3/7(x - 4)
y + 5 = -3/7x + 12/7
y = -3/7x - 23/7
First, put each grade in terms of x. Most grades are compared to Sophomores, so I made that x
Freshmen = x + 10
Sophomores = x
Juniors = x + 20
Seniors = (x + 10) + 7 = x + 17
Then, the total number of students = 363, so we’ll make an equation that adds them all up in terms of x to equal 363
(x + 10) + x + (x + 20) + (x + 17) = 363
Combine like terms:
4x + 47 = 363
Subtract 47 from both sides:
4x = 316
Divide both sides by 4:
x = 79
The question was how many seniors there are. Seniors were x + 17, so 79 + 17 = 96
