Answer:
Step-by-step explanation:
Gradient of a line =( y2 - y1)/x2 - x1
From the question, x1=4,y1=-1,x2=1,y2=0.
Therefore, substitute for these values in the above formula
m = 0-(-1)/1-4
= 0+1/-3
= -1/3.
Therefore, y-y1/x-x1 = -1/3
y - y1 = -1/3(x - x1)
y - (-1) = -(x-x1)/3
y+1 = - (x - 4)/3
Multiply through by 3
3y+3= -x+4
3y +x=4-3
x+3y= 1
Therefore the answer is A.
Answer:

Step-by-step explanation:
This question is asking you to insert two equations, f(x) and g(x), into the equation g(x) - f(x). This will lead to the equation below.

Now we can solve for the equation.

Answer:
5.5 minutes
Step-by-step explanation:
Fill in the given information and solve for t.
75 = -15cos(2πt/15) +65
-10/15 = cos(2πt/15)
t = 15/(2π)arccos(-2/3) ≈ 5.492
The volume reaches 75 dB about 5.5 minutes after the truck arrives.
Answer:
(p+e)/(r-n) = x
Step-by-step explanation:
p + nx=rx-e
Add e to each side
p +e+ nx=rx-e+e
p +e+ nx=rx
Subtract nx from each side
p +e+ nx - nx=rx-nx
p+e = rx -nx
Factor out x
p+e = x(r-n)
Divide each side by (r-n)
(p+e)/(r-n) = x(r-n)/(r-n)
(p+e)/(r-n) = x