Answer:

-12x = 60
Step-by-step explanation:
This is the type of problem that you just have to do a bunch of times until you get it right -- I don't think there's anything I can tell you that'll help you immediately. Ask for your teacher for more exercises of this sort or look it up online.
Good luck!
X + y = 16 (1)
x/y = 3 (2)
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x + y = 16
x = 16 - y
1. Substitute x into equation 2
16-y/y = 3
16 - y = 3y
16 = 4y
y = 4
2. Now substitute y into equation 1
x/y = 3
x/4 = 2
x = 12
Therefore, x = 12, y = 4
Answer:
(x,y)= (2/15, -(62/15)
Step-by-step explanation:
Answer:
B
Step-by-step explanation:
9514 1404 393
Answer:
B. (x +4)² +(y +5)² = 64
Step-by-step explanation:
The equation for a circle with center (h, k) and radius r is ...
(x -h)² +(y -k)² = r²
Filling in your given values, you have ...
(x -(-4))² +(y -(-5))² = 8²
Simplifying, you get ...
(x +4)² +(y +5)² = 64 . . . . . . . matches choice B
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<em>Additional comment</em>
As you learn more different "standard form" equations, it may be helpful to keep a list, along with reminders of what the variables stand for and how the equation is used.