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Simplify 0.9x + 1.26 - 2.3 + 0.1 * x to x - 1.04
add 1.04 to both sides
simplify 1.6 + 1.04 to 2.64
Answer: x = 2.64
When you arrange the N points in sequence around the polygon (clockwise or counterclockwise), the area is half the magnitude of the sum of the determinants of the points taken pairwise. The N determinants will also include the one involving the last point and the first one.
For example, consider the vertices of a triangle: (1,1), (2,3), (3,-1). Its area can be computed as
(1/2)*|(1*3-1*2) +(2*-1-3*3) +(3*1-(-1)*1)|
= (1/2)*|1 -11 +4| = 3
They have 5 3/4 ft
4+1=5
1/4+2/4=3/4
but hey, its not the length of your wood that matters, its how you use it XD