Answer:
221
Step-by-step explanation:
Substitute x = 7 and y = 8 into the expression
5(7)² - 3(8)
= 5(49) - 24
= 245 - 24
= 221
First we need to convert the given equation to standard form, only then we can find the center and radius of the circle.
![x^{2} + y^{2} +18x+14y+105=0 \\ \\ x^{2} +18x+ y^{2}+14y=-105 \\ \\ x^{2} +2(x)(9)+ y^{2}+2(y)(7)=-105 \\ \\ x^{2} +2(x)(9)+ 9^{2} + [y^{2}+2(y)(7)+7^{2}] =-105+9^{2}+7^{2} \\ \\ (x+9)^{2}+ (y+7)^{2}=25 ](https://tex.z-dn.net/?f=%20x%5E%7B2%7D%20%2B%20y%5E%7B2%7D%20%2B18x%2B14y%2B105%3D0%20%5C%5C%20%20%5C%5C%20%0A%20x%5E%7B2%7D%20%2B18x%2B%20y%5E%7B2%7D%2B14y%3D-105%20%5C%5C%20%20%5C%5C%20%0A%20x%5E%7B2%7D%20%2B2%28x%29%289%29%2B%20y%5E%7B2%7D%2B2%28y%29%287%29%3D-105%20%5C%5C%20%20%5C%5C%20%0Ax%5E%7B2%7D%20%2B2%28x%29%289%29%2B%209%5E%7B2%7D%20%2B%20%5By%5E%7B2%7D%2B2%28y%29%287%29%2B7%5E%7B2%7D%5D%20%20%3D-105%2B9%5E%7B2%7D%2B7%5E%7B2%7D%20%20%5C%5C%20%20%5C%5C%20%0A%20%28x%2B9%29%5E%7B2%7D%2B%20%28y%2B7%29%5E%7B2%7D%3D25%20%20%0A%20%20)
The standard equation of circle is:

with center (a,b) and radius = r
Comparing our equation to above equation, we can write
Center of circle is (-9, -7) and radius of the given circle is 5
so you can either do pounds per dollar or dollars per pound:
pounds per dollar : about 0.71 lbs / $
dollars per pound : $1.40 / lb
i hope this helped, based on the question i believe that it is dollars per pound but its good to know both and have a nice day
Answer:
The answer is 3
Step-by-step explanation:
7.5 m
---------
5
7.5(2)=15
-------------
5
15
--- =3
5
Answer: ⇒ The finance charge = $77
Step-by-step explanation:
Given: The cost price of DVD player= $295
Since, Tim agreed to pay $31 per month for 12 months .
Therefore, the total amount paid by Tim= 
The finance charge =
⇒ The finance charge =
⇒ The finance charge =$77