3a + 6b = 45
2a - 2b = -12....multiply by 3
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3a + 6b = 45
6a - 6b = - 36 ...(result of multiplying by 3)
---------------add
9a = 9
a = 1
3a + 6b = 45
3(1) + 6b = 45
3 + 6b = 45
6b = 45 - 3
6b = 42
b = 7
solution is : (1,7)
Answer:
B. 1 and -2
Explanation:
First, add up the equations:
x-x+3y+y=4
4y=4
y=1
Now, plug y into any of the original equations above and solve for x:
-x+1=3
-x=2
x=-2
Therefore, the answer is B. 1 and -2
Answer:
6.
Step-by-step explanation:
If each assignment is worth -3, you can divide 18 (amount of points changed) by 3 (each assignment's affect) to get 6.
Answer:
2 points
Step-by-step explanation:
10-14=-4
-4+6=2 or
10+6=16
16-14=2