I would solve the first equation for x and then sub that value into x in the second equation. That's the easiest way. x - 2y = 3 solved for x is x = 2y+3. Now sub that in for x in the second equation: 5(2y+3)+3y=2 and 10y + 15 + 3y = 2. 13y = -13, and y = -1. Now sub that y value into either equation to solve for x: x = 2(-1) + 3 gives us an x value of x = 1. Therefore, your solution to this system is (1, -1), first choice above.
(n-2)multiple 180 degrees the formula for finding the sum of all angles in a polygon regular here n represents the number of sides of the polygon.
77(7) = 539, the total points of all her tests
539 - 18 + 81 = correct total points = 602
602/7 = 86 which is the new average
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Formula
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Area of circle = πr²
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Find Area of circle
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Area of circle = 3.15 x 3²
Area of circle = 28.26 unit²
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Answer: Area = 28.16 unit²
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