area rule for a parallelogram similar and different to the area rule of a rectangle?
818692
They are both base times height; however, in a rectangle the base and height are always sides of the rectangle and in non-rectangular parallelograms, one of them will not be the same as a side.
955408
the formula is half the height times the base.  But here's why:\n\nFirst consider a rectangle.  You know the surface to be height times width.  Now cut the rectangle in two pieces, along a diagonal.  You end up with two triangles. Furthermore, the sides of these triangles are the same, thus the triangles themselves are equal. The surface of each has to be half that of the surface of the rectangle.\n\nFor triangles with a right angle in them, you have proven 0.5*h*b to be correct.  But each triangle will work.  If you have a triangle without a right angle, you can always find a way to split it in two smaller triangles, each having a right angle, and process each part separately.\n\nYou could also cut a parallelogram in two equal parts (again: cut a diagonal) and end up with two equal triangles, not having a right angle.
572318
1) Let x:the length , y:the width of the picture.Note:x,y>0\nThe first equation we have is : x=y+4 (1)\nThe combined area has the length is x+4,the width is y+4       \nso the second equation we have is: (x+4)*(y+4)=140 (2)\nReplace (1) in (2)-->(x+4)x=140--> x^2+4x-140=0 -->x=10 or x=-14 .since x>0 then x=10(cm)-->y=6(cm).\n2)  Let x: the length,y:the width.Note:x,y>0\n    The first equation we have is x=y+3 (1)\n    The second is: the area=x*y=550 (2)\n    Replace (1) in (2)--> (y+3)y=550--> y^2+3Y-550=0 --> y=22 or y=-25.Since y>0 then y=22(cm)-->x=25(cm)\n3)  Let x,y:two positive integers.Supposed that x>y>0 \n    we have two equation:x*y=240(1) and x=y+8(2)\n    Replace (2) in (1)-->y(y+8)=240--> y^2+8y-240=0 -->y=12 or y=-20.Since y>0 then y=12-->x=20.
414775
Not all Parallelograms are rectangles, But all rectangles are parallelograms.
573267
It's the formula for the area of a regular polygon\n\nArea = 1/2 times apothem times perimeter\n\n(apothem = perpendicular distance from center to midpoint of a side)
830003
i don;t know all of them, but here are a few:\n-rectangle\n-square\n-rhombus\n-parallelogram\n-kite\n-trapezoid\n-and closed abject with four sides!\n-cyclic quaDrilateral     \n-cyclic-inscriptable \n\ncheck out the site dr. math for more info on quadrilaterals!
912774
Yes, what's the question? I'll take a guess ...\n\nIf your rectangle is divided into ten equal pieces, then each one will be a tenth, so if you shade 3 for example, that will be 3 tenths ... any help?
6341
Area of a Rectangle\nA rectangle is a good, simple shape to begin with. The area of a rectangle is equal to the product of the length of its base and the length of its height. The height is a segment that is perpendicular to the base. For a rectangle, the base and height are often called the "length" and the "width", and sometimes the height is referred to as the "altitude." \n\nArea of a Parallelogram\nTo find the area of a parallelogram, we can use the same formula that we used for the area of a rectangle, multiplying the length of the base times the length of the height. \n\n\n\nLet's find the area of a parallelogram that has a base of 23 cm and a height of 7 cm. If we substitute the values into the formula, we find that the parallelogram has an area of 161 square centimeters\n\n&...
741830
the ratio is 1:2 or 1/2\n\noh, by the way it goes like this:\n\nassuming the length of each side of square A is a, then the area is a^2.\n\nsince, the vertices of the smaller square (A) is the midpoint of the sides of the big square(B), using the diagonal of square A, we can find the sides of the bigger square.\n\nThe diagonal is a*squareroot of 2, in which when we square to get the area ===>  gives us 2a^2.\nThus, the ratio is between Square A' area (a^2) and B's area (2a^2) is 1:2 or 1/2
809433
1.rectangle\n\n2.trapezoid
1109720
Simple answer: Any non-square rectangle can have a line drawn within it parallel to the short side that partitions it into a square and a smaller rectangle. If the long side of the rectangle is a and the short side is b, the new rectangle will have dimensions of b x (a-b). If this is not obvious to you, remember that one side of the rectangle is the side of the square (which has dimensions b x b), and the other is the part of the long side which is not occupied by the square (thus having a length equal to the length of the long side minus the length of the square). \n\nNow, some rectangles, when so partitioned, have the property that the new rectangle formed by the partition will have the same ratio between the lengths of its sides as the original rectangle. That is, a/b = b/(a-b). Such rectangles are called golden rectangles, and the ratio of the sides of a golden rectangle is called the golden ratio.\n\nThe golden ratio is easily shown to be both irrational and algebraic. Irrationality is proven by contradiction: note that all rational numbers can be represented in lowest terms - that is, as the ratio of two integers that have no common factors other than 1. However, the golden ratio cannot be represented in lowest terms, since if some ratio a/b were a representation in lowest terms, b/(a-b) would be a valid representation in even lower terms, which contradicts our statement that a/b is in lowest terms. Q.E.D.\n\nComputing the golden ratio is done by solving the equation we provided: a/b = b/(a-b). We arbitrarily choose b to be 1 - we could let b be anything, but letting b be 1 makes the ratio a/b much easier to compute, since it will simply be equal to a. Thus we have a=1/(a-1). Multiplying, we get a(a-1)=1 and from that a² - a = 1 Putting this in standard form, we have a² - a - 1 = 0, which shows that the golden ratio is algebraic, since our formula for computing it IS a polynomial - this stands in contrast to many other fundamental constants like pi and e, which cannot be expressed as a root of any polynomial of any degree (that is, they are non-algebraic).\n\nCompleting the square then yeilds:\n\na² - a - 1 = 0\na² - a + 1/4  = 5/4\n(a - 1/2)² = 5/4\na - 1/2 = ±√(5)/2\na = (1 ± √5)/2\n\nHowever, since the golden ratio is a ratio of lengths, and all lengths are positive, we know that it cannot be (1 - √5)/2, since that is negative. Thus the golden ratio is (1 + √5)/2 exactly.
158697
his saying the area not the other side.\na= bh/2\nu know that this parallelogram is a rectangle and if u put adiagonal angle abc is a right. so u'll just use the formula\n12*13 over 2\n=78 units.
981115
that way you can remember the formula with generic terms like L and W then later insert the corresponding numbers.\n\nlength times width equals area\nL * W = A\nl2" * 12" = 144 square inches
583405
The area of a kite is half the product of the diagonals. Note: This formula works for the area of a rhombus as well, since a rhombus is a special kind of kite. Note that the diagonals of a kite are perpendicular.\n\nJoe is right that you can do it as two triangles, but you'll get the same result.\n\nLook at the image in the link below.  Notice how the outside rectangle has double the area of the inside kite.  Notice also how the height and width are the same.  So it is exactly half the height times the width.
426495
It depends on what shape you want to know the area.\n\nSimple shapes have formulas. (such as a circle's area is Pi*r*r)\n\nComplex shapes which have pattern.(you know the equation of lines that form the shape), calculus is used to find the area.\n\nIf a shape is not ordinary. You should draw lines to grid it and count the area square by square.\n\n-Hope this would help-
73554
ZERO (O)  NO RECTANGLES..\n\n\nCHESS BOARD HAVE ONLY SQUARES..
992822
Let the breadth of each red rectangle be x\n\nSo, area of red portion = 4x + x(3-x)\n\nSo, area of white portion is (4-x)(3-x)\n\nSo, 4x+x(3-x) = (4-x)(3-x)\nor 4x + 3x -3x^2 = x^2 -7x+12\nor 4x^2-14x+12 = 0\nor 2x^2-7x+6 = 0\nor 2x^2-6x-x+6=0\nor(2x-1)(x-3)=0\n\nx=1/2 or 0.5 foot is the reasonable answer.