2x + 3y = 45
x + y = 10......y = 10 - x
2x + 3(10 - x) = 45
2x + 30 - 3x = 45
-x + 30 = 45
-x = 45 - 30
-x = 15
x = -15 <====
and y = 25
The answer is A. To understand that, you need to put it in order by the x's and the y's to get x^2-6x + y^2-16y = -48. Now complete the square on both the x and the y terms to get (x^2-6x+9) +(y^2-16y+64) = -48+9+64. Rewriting that in vertex form on the left and doing the math on the right gives you
(x-3)^2 + (y-8)^2 = 25, which shows you a center of (3,8) and a radius of 5.
The best estimate would be 121/15 = 8.1
Are you sure it is correct because for each one your just doubling the number. 2+2=4. 4+4=8. 8+8=16. I think its suppose to be 16+16= 32 and so on, but I may be wrong
Answer:
D
Step-by-step explanation:
It's the only thing not listed aka the number of math problems.