9514 1404 393
Answer:
A
Step-by-step explanation:
Your friendly local graphing calculator or spreadsheet can tell you the quadratic regression equation. It best matches choice A.
what makes it irrational is the

which does not change from one zero to the other. so if one root its irrational the other one also is. Answer A
The total cost function is the sum of the two given functions, and this is equal to:
c(t) = 190 + 70*t
<h3>
How to find the linear function for the total cost?</h3>
We know that:
- The plumber charges p(t) = 115 + 25*t
- The electrician charges e(t) = 55*t + 75.
If she hires both of them for the same time t, then the total cost function will be given by the sum of the two above functions, we will get:
c(t) = p(t) + e(t)
c(t) = (115 + 25*t) + (55*t + 75)
c(t) = (115 + 75) + (55*t + 25*t)
c(t) = 190 + 70*t
If you want to learn more about linear functions, you can read:
brainly.com/question/4025726
Answer:
East and west side= 5 foot
South and north side = 10 foot
Area = 50 foot^2
Step-by-step explanation:
We know that:
East and west fencing cost= $4 per foot
South and north fencing cost $2 per foot
So, we can consider:
x= south and north fencing
y= east and west fencing
Then we create an equation representing the case:
Total cost = (south+north)*$2 + (east+west)*$4
80 =(x+x)*2 + (y+y)*4
80 =(2x)*2 + (2y)*4
80 =4x + 8y
80 =4*(x+2y)
80/4 =x+2y
20 = x+2y
x= 20-2y
We can calculate the area as width * length:
Area = length * width
Area= x * y
Area= (20 - 2y) * y
area= 20y - 2y^2
Next step is to find the "y" value for the maximum area so you can derivate and equal to 0 to find maximums:
d(20y - 2y^2)/dy = 20 - 2*2y = 20 - 4y
20 - 4y = 0
20 = 4y
y = 20/4
y = 5
If y = 5, then:
x = 20 - 2y
x = 20 - 2*5
x = 20 - 10
x = 10