to find the radius of x^2+y^2-10x+6y+18=0, we must complete the square:
x^2 - 10x + y^2 + 6y = -18
Then:
x^2 - 10x + 5^2 - 5^2 + y^2 + 6y + 9 - 9 = -18
Collecting all three constants on the right-hand side, r^2 = -18 + 25 + 9 = 16
Then r = +sqrt(16) = +4 (answer)
Answer:
Verizon Wireless offers better plan
Step-by-step explanation:
Now it is easiest to calculate an yearly cost for both companies.
First calculate cost for Verizon
If y is annual payment and x is monthly payment
Relation is
y = 20 + 12x
y = 20 + (12)(20)
y = 260
So for Verizon wireless, annual amount is $260
Now calculate cost for Consolidated Communication
If y is annual payment and x is monthly payment
Relation is
y = 10 + 25x
y = 10 + (12)(25)
y = 310
So for Consolidated Communication, annual amount is $310.
Here by comparison we can see that the offer of Verizon Wireless is better in long term.
Triangle Area = .5 * base * height
48 = .5 * (x +4) * x
48 = (.5x + 2) * x
48 = .5x^2 + 2x
.5x^2 + 2x -48 = 0
x = 8
base = 12
