Answer:
<em>C. 15</em>
Step-by-step explanation:
Assuming that these segments formed from each parallel line are proportional, x/5 = x-6/3.
Now cross multiply by multiplying each denominator by the opposite numerator, this is so the denominators or bottom numbers of each fraction will cancel.
x/5 = x–6/3 → (3)(x/5) = (3)(x–6/3) → 3x/5 = x–6 →
(5)(3x/5) = (5)(x–6) → 3x = 5(x–6) → 3x = 5x – 30.
The last step is to do the basic algebra to find x:
3x = 5x – 30
–5x –5x
[5x will cancel when you subtract both sides by 5x]
-2x = -30
(-1) (-1)
[2 negatives make a positive when -1 is multiplied by an expression with a negative coefficient]
2x = 30
÷2 ÷2
[divide both sides by 2 to simplify 2x to x]
x = 15
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You can also check that both sides are proportional because
5 → x
x = 15
5 → 15
3 → x – 6
x = 15
3 → 9
5 × <u>3</u> = 15
3 × <u>3</u> = 9
There are two cases to consider.
A) The removed square is in an odd-numbered column (and row). In this case, the board is divided by that column and row into parts with an even number of columns, which can always be tiled by dominos, and the column the square is in, which has an even number of remaining squares that can also be tiled by dominos.
B) The removed square is in an even-numbered column (and row). In this case, the top row to the left of that column (including that column) can be tiled by dominos, as can the bottom row to the right of that column (including that column). The remaining untiled sections of the board have even numbers of rows, so can be tiled by dominos.
_____
Perhaps the shorter answer is that in an odd-sized board, the corner squares are the ones that there is one of in excess. Cutting out one that is of that color leaves an even number of squares, and equal numbers of each color. Such a board seems like it <em>ought</em> to be able to be tiled by dominos, but the above shows there is actually an algorithm for doing so.
The 3rd one because you have to get the y-intercept also which is -6
Answer:
-12
Step-by-step explanation:
if a=-2 and b=-5
(18-(-2×-5))+4(-5)
(18-(10))-20
8-20
-12
just gotta plug in the given into the equation