30b + 100u = 900
5b + 25u = 200....multiply by -6
------------------
30b + 100u = 900
-30b - 150u = - 1200 (result of multiplying by -6)
------------------add
-50u = - 300
u = 6 <== upgrated phones sold
30b + 100u = 900
30b + 100(6) = 900
30b + 600 = 900
30b = 900 - 600
30b = 300
b = 10 <== basic phones sold
Answer:Perimeter is the measurement all around the shape. So, to do this we wolud need to add this measurments together
Step-by-step explanation:
8.2+3.9=12.1
12.1+4.5=16.6
Answer:16.6cm
Answer:
0,1.5
Step-by-step explanation:
y = 510 - 60x
We want to find the domain or the x values where x represents the time
We need to determine the possible values for x
Y cannot be greater than 510 or less than 0. 510 means they have not started the trip, and 0 means they have arrived
510 = 510 -60x
Subtract 510 from each side
510-510 = 60x
0 = 60x
The smallest value of x can be 0
0 = 510 - 60x
Subtract 510 from each side
-510 = 510-510-60x
-510=-60x
Divide by -60
-510/-60 = -60x/-60
8.5 = x
The maximum value of x is 8.5 hours
So x must be between 0 and 8.5 inclusive.
