> multiply the second equation by 2 and add it to the first equation.
2(-6x - 7y = -10)
-12x -14y = -20
8x + 14y = 4
-12x - 14y = -20
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- 4x + 0 = - 16
x = -16/-4
x = 4
> use x = 4 in either equation to find y
8(4) + 14y = 4
32 + 14y = 4
14y = 4 - 32
14y = -28
y = -28/14
y = -2
Answer: 81 units²
Step-by-step explanation: To solve this problem, remember that the formula for the area of a square is 4s.
Therefore, since the perimeter of the given square is 36, we have 36 = 4s and dividing both sides by 4, 9 = s.
Now, remember that the formula for the area of a square is s² and since the length of a side of the given square is 9, we have (9)² or 81.
So the area of a square that has a perimeter of 36 is 81 units².
The increase in price was 10%
2.5*.1=.25
2.5+.25=2.75
hope this helps