The answer is -a + b = 0
If she wants to solve <span>a system of linear equations by elimination and if one equation is unknown, one of the solutions in the unknown equation must be negative:
Known equation: a + b = 4
Unknown equation: -a + b = ?
We know that a = 2 and be = 2, thus:
</span>Unknown equation: -2 + 2 = 0
The general form of the equation is -a + b = 0
Let's check it out:
Known equation: a + b = 4
Unknown equation: -a + b = 0
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Add them up: 2b = 4
b = 4/2 = 2
a + b = 4
a = 4 - b
a = 4 - 2
a = 2
So, the second equation is correct.
I think because the number of blocks is different, but the proportion of space can be filled in the same.
The correct answer in here is C. The second arc should be centered at C. We say this because <span>s the parallel line has to pass through C, then the second arc should be centered at C. Hope this is useful for you</span>
