the formula to find the area of a trapezoid is \n1/2(b1+b2)h. \nor\n.5(base1+base2)height\n\none trapezoid is missing is height and im not sure how to find it. the base1 of the figure is 20yd, and the base2 is 10 yd. the area is 450 sq yd. x, the height, = ?
120837
The height is 30 yd.  Just plug in what the problem gives you into the formula, and solve for the variable or the missing information.  \n\nArea = 1/2(Base.1 + Base.2)h\n\n450 = 0.5(20+10)*h\n450/0.5 = (30)*h\n900 = 30*h\n900/30 = h\n30 = h\n\n100% possitive
166712
Surface areas and lateral areas are always fun to find.  Surface areas for right prisms and cylinders is always the sum of the lateral area and two times a base.  (Lateral area is the sum of all the surfaces that aren't bases.)\n\nIn the case of a cylinder, the lateral area is really a rectangle - imagine cutting open a roll of toilet paper.  The length is really the circumference of the top (base) and the height is, well, the height of the roll.  So the lateral area is 2*pi*r*h.\n\nThe surface area is the lateral area plus two bases.  A base in this case is given by pi*r^2.  So the total surface area is 2*pi*r^2 + 2*pi*r*h.\n\nThe idea behind lateral and surface areas will carry over when you start working on right prisms (if you're not already doing those).  Lateral area is, in the case of a prism, the perimeter of the base (similar to cylinders, except we used "circumference" in place of "perimeter") times the height of the prism.  And the surface area is the lateral area plus two bases - in this case, the bases vary (you may have squares, triangles, trapezoids, etc.), so your formula for the total surface area will vary as well.\n\nThis is probably more than you wanted to know, but it's always good to relate things you know to things that you're learning.
221531
the formula for volume of a cylinder is V = h * pi * r^2.\nAlternatively, the surface area is A = h * pi * r * 2.\n\nSo, if you have either the surface area or the volume, you can calculate for the height.\n\nH = Volume / pi * r^2\nH = Area / pi * r * 2
377776
First use the Pythagorean Theorem.\n\nThe hypotenuse is 20. One of the legs has length x. Call the length of the other leg y.\n\nx^2 + y^2 = 20^2\nx^2 + y^2 = 400\n\nNow solve for y in terms of x.\n\ny^2 = 400 - x^2\ny = sqrt(400 - x^2)\n\nNow, since the triangle is right, the two legs are the altitude (or height) and the base.\n\nA = (1/2)*b*h\nA = (1/2)*x*y\nA = (1/2)*x*sqrt(400-x^2)\n\nThere's the area in terms of x!
350480
1) Area of a trap = (a+b)h/2\n88=(12+b)(8)/2\n2*88=(12+b)(8)\n2*88/8=(12+b)\nb=2*88/8 - 12\nb=10\n\n2) lateral surface area S = p*s/2\np = perimeter, s=slant height\nperimeter of a pentagon of base length 3 = 5*3=15\nS=15*5/2\nS=37.5
114451
If an object is a parallelogram, we define its area to be its length multiplied by its height. Rectangles and squares are common parallelograms.\nIf you cut a parallelogram in half along its diagonal, you get a triangle with the same width and height, but half the area. Thus the formula for the area of a triangle is (1/2)*base*height where the name "base" has replaced the now meaningless label of "length".\nUsing these two formulas, you should be able to find the area of any polygon (a closed shape with straight sides) by cutting it up into these shapes of known area. For example, a trapezoid can be cut up into a rectangle and two triangles.\nThe perimeter of a polygon is the easiest measure. Just add up the lengths of all the sides.
4491
sorry i made a mistake....this is correct...\ndivide the base by 2.  Now you have a right triangle.  the height is the same, but the base is now 3.  pygathora (spelling, whatever) theorm is A squared + B squared = C squared.  c is the side opposite the right angle, a and b are the other sides.  so 3 squared + 4 squared is 9 + 16 = 25. The square root of 25 is 5, so that is the length of the side.  the volume = area of base times height.  Area of a triangle is 1/2 base times height.  so 3 (one half of 6) times 4 = 12.  times this by height of 8 = 96 cubic units. largest rectangular side is the 6 (the longest side) times 8 = 48 units squared. hope this helped.  the lateral area is the area of the sides added together. so C times 8 = 40 (area of one side)  add the other side of equal area (the C from the second triangle we got when we split the first one) 40 + 40 = 80.  Add the third side of length 6 times 8 = 48.  80 + 48 is 128 (in units squared).  or all sides added up 5 + 5 + 6 = 16 times 8 = 128.
53725
Area = Pi times the radius squared (A=pr2)\nIf you need to know how to find the radius, go here:\n\nhttp://math.about.com/library/blcircle.htm
288712
Are you talkin about a trapezium or a trapezoid.\nif its a trapezium,here's how : \nlet the height be "h".\ndrop two perpendiculars equal to h on the base.the lengths b&#92;w the perps.is 6 units.therefore the rest of the length is 10.each individual length to the left of the perp is 5 units.\nin the triangle with the diagonal,the side adjacent to the angle with the base and diagonal is 6+5=11\ntherefore the angle is cos^-1(11/12)=a\ntherefore tan a=h/11\ntherefore h=11tan a\nanswer is height,h=4.795831523
40081
V=1/2(b1+b2)*h*w  where b1 and b2 are the two parallel sides of the trapezoid and h is the height and w is the width.
44992
Yep, it's the Pythagorean theorem question.\n\nA^2=B^2+C^2\n\nA is always the hypotenuse.\n\n20^2 = 400\n\n400 = 144 + B^2\n256 = B^2\n16 = B\n\nSo the length of the last side is 16 yards.\n\nHence, the total length is A + B.\n\n12 plus 16 is 28 yards total of fencing.\n\nThe area of an enclosed yard is one yard squared.\n\nBut if you're curious as to what the area is of the triangle created by the house and the fencing, then it's 1/2(B*C)\n\n1/2*192= 96yd^2 is the area of the triangle.
230835
If this is a right triangle, the formula for finding the area is 1/2 BH (base x height).  Therefore, the formula you want for this problem is 1/2[x(x-3)]=35.
510642
Let x be the length for the square and 14-x for the triangle.\n\nThe area of the square is (x/4)^2 = (x^2)/16.\n\nThe height of the triangle is sqrt(3)(14-x)/6 and the base of the triangle is (14-x)/3, so the area of the triangle is\n\n1/2 bh = [(14-x)/6] [sqrt(3)(14-x)/6] = (14-x)^2 sqrt(3)/36\n\nTotal area A = (x^2)/16 + (14-x)^2 sqrt(3)/36\n\nA = [9x^2 + 4(x^2 - 28x + 196) sqrt(3)] / 144\n\nA = [(9 + 4 sqrt 3) x^2 - (112 sqrt 3) x + (784 sqrt 3)] / 144\n\ndA/dx = [2(9 + 4 sqrt 3) x - (112 sqrt 3)] / 144 = 0\n\n(9 + 4 sqrt 3) x = 56 sqrt 3\n\nx = (56 sqrt 3) / (9 + 4 sqrt 3) = 6.0895 meters  (Answer)\n\nThe area of the square is 2.32 m^2.  The area of the triangle is 3.01 m^2, and the total area is 5.33 m^2.
391001
C=2(Pi)r or diameter times Pi\nI don't know how to solve the problem cause not enough info is given. Does it say what C equals?\n\nv = lwh . H stands for the height. Does it say what v equals?\n\na= 1/2h(b1+b2) b1 is base 1. Does it say waht the area is?\n\nProvide more info please. :)
677084
A cone and pyramid have one thing in common, the base area is proportional\nto the square of the height.  If you keep the angles and overall shape the\nsame and just increase the size (like a slight zoom of a camera lens), the\nbase area is some constant times the square of the height:  A=cH^2.  The "c"\nis a constant that will eventually divide out.  Also, the volume is\nproportional to the cube of the height:  V=kH^3.  We want to find out how k\nmust relate to c.\n\nConsider two cones with identical shapes: one has height H, one has height\nH+h.  "h" is extremely small.  If H were 10 meters, h would be a millimeter.\nThe base area and volume for the first are A1=cH^2 and V1=kH^3.  The other's\narea and volume are A2=c(H+h)^2 and V2=k(H+h)^3.\n\nIf we subtract the larger smaller volume from the larger volume, we get the\nvery thin sheet at the bottom.  If h is small enough, the thin sheet will\nhave area A1=cH^2 and height h.  The thin sheet will have a volume (cH^2)h.\nIf you don't say that h is very small, then the sheet will have a more\ncomplex volume formula.  We now have V2-V1=(cH^2)h.  Let's do the algebra:\nk(H+h)^3- kH^3=(cH^2)h\nkH^3+(3kH^2)h+(3kH)h^2+kh^3  -  kh^3  = (cH^2)h\n(3kH^2)h + (3kH)h^2 + kh^3 =(cH^2)h\n\nNow, the limits:\n\n"h" is tiny, so the second and third terms are extremely small compared to\nthe first.  They are like adding a penny to a million dollars.  They really\ndon't count enough to keep.  Limit theory lets us drop them under the\ncircumstances.  This yields:  (3kH^2)c=(cH^2)h.  Divide out common terms and\nget:  3k=c, or k=(1/3)c.  Put this in the original formula for volume:\nV=kH^3=(1/3)cH^3=(1/3)(cH^2)H=(1/3)AH.  Volume equals (1/3)Base area times
392953
surface area = (2 * pi * r^2) + (2 * pi * r * h)\nh = 5, surface area = 100 (put in units later)\n\n100 = (2 * pi * r^2) + (2 * pi * r * 5)\n2pi*r^2 + 10pi*r - 100 = 0\n\nNow bring in the best equation in the world. (Quadratic Formula)\nx = (-b +- sqrt(b^2 - 4ac)) / 2a\n\nr = (-10pi +- sqrt(100pi^2 + 800pi) / 4pi\n\nThrow the negative out, because length cannot be negative.\n\nr ~ 2.21cm
558462
Assuming you mean a regular hexagon, then with the 30-60-90 relationship, you should get that half the length of a side is 2.\n\nSo, the area of that yellow triangle in the link below is\n.5 * 2 * 2 * sqrt(3) = 2 * sqrt(3)\n\nThere are 12 triangles, so the area is 24 * sqrt (3).