What is the formula for a circle graph?
369810
Find the fraction/decimal/percent/whatever. Then, find how big this is for 360 degrees. For example, say you have 41%. Just find 41% of 360. If this is a problem, then just multiply the fractin/decimal/percent/whatever by 360.
511828
I want to point out first that the formula for perimeter of a circle is (pi)d or 2(pi)r, not (pi)r^2- (pi)r^2 is for the area!\n\nAnyway, P= (pi)d\n         = 8pi\nDivide that by two since it's just a half circle\n         =4pi\nAdd 8 to that, and there you have it, the perimeter!\n\nFinal Answer- 4pi+8 or 20.56cm^2
33948
u know general equation of circle is\n(x-h)^2+(y-k)^2=r^2\nwhere h and k are x and y coordinates of center of circle and r is radius of circle.\njust put the known values of h,k and r to get the equation.\nhey,i did it.
224253
You know that the area of a circle is given by:\nA = (pi)(r²)\n\nYou also know that the radius is half the diameter, so\nr = d/2\n\nYou may substitute this to the area formula:\nA = pi * (d/2)²\nA = pi * d²/4\nA = (pi)(d²)/4\n\n^_^
807243
I'm not sure how far I'll get with this one, but I'll give it a try.\n\nLet the center of the circle be at (p,0), so the equation of the circle is (x-p)^2 + y^2 = a^2, with a>p.  The chord is y = mx, and we want to find where the chord and circle intersect.\n\n(x-p)^2 + m^2 x^2 = a^2\nx^2 - 2px + p^2 + m^2 x^2 = a^2\n(m^2 + 1) x^2 - 2px = a^2 - p^2\n\nSolve by completing the square (details omitted) to get\n\nx = {p +/- sqrt[m^2 (a^2 - p^2) + a^2]} / (m^2 + 1)\n\nThe center of the chord (hence center of the circle with chord as diameter) is at x = p / (m^2 + 1), with y = mx = mp / (m^2 + 1).  The radius is sqrt[m^2 (a^2 - p^2) + a^2] / (m^2 + 1), so the equation of that circle is\n\n[x - p / (m^2 + 1)]^2 + [y - mp / (m^2 + 1)]^2\n  = [m^2 (a^2 - p^2) + a^2] / (m^2 + 1)^2\n\nIf q = m^2 + 1, then by clearing fractions, we get\n\n(qx - p)^2 + (qy - mp)^2 = m^2 (a^2 - p^2) + a^2\n\nI'm not going to check my work, but those are the answers I ended up with.
991890
Try the 2-2 pattern. it's the best way. The 3 is done with that criss-cross pattern, but the 2-2 allows you to continue the circle, just make it have a big radius
524037
The general form of the equation of a circle is\n\n(x - a)^2 + (y - b)^2 = r^2\n\nwhere (a, b) is the center and r is the radius.  So for your circle,\n\n(x - 4)^2 + (y - 7)^2 = 36\n\nthe radius is 6.  (And FYI, the center is at (4, 7).)\n\nEDIT:  For your second question, the answer is false - the coordinates would be (3, -5).
387856
All these problems are available in coordinate geometry text books.  For the problem 1)\n\nThe equation of the circle with A(x1,y1)and B(x2,y2) as end points of diameter is (x-x1)(x-x2) + (y-y1)(y-y2) = 0\n\nSimply substitute A(2, -3) and B(8,5) wou get \n(x-2)(x-8) + (y+3)(y-5) = 0\nthat is, x^2 - 10x+16 + y^2 -2y -15 =0\nOr, x^2 + y^2 - 10x -2y + 1 =0\n\nThis is the required equation.\n\n2) In standard form of parabola y^2 = 4ax, the origin (0,0) is vertex, S(a,0) is focus and x + a = 0 is the equation of directrix.  In the present case, the focus is at (2,3).  this means the coordinates of vertex are (0,3)and the equation of diretrix is x + 2 = 0.  Therefore the equation of the parabola is (y-3)^2 = 4. 2. (x-2)\nOr y^2 -6y -8x + 25 =  0\n\nSimilarly attempt the problems 3 & 4
181035
a circle's circumference is define as 2Pi x Radius\n\nin this case 2 x 3.14... x 3 so your answer is c
513696
The area equation of a circle is pi r^2. And, a circle has an arc measure of 360. Since the shaded region has that of 40, it would be 40/360 = 1/9 of a circle.\nA = 1/9 pi r^2 = 59\npi r^2 = 59 x 9\nr^2 = 59x9/pi\nr = sqrt 59 x 9/pi = 13! =)
226433
The circle's center is at (4, -1).  Therefore its radius is sqrt((6-4)^2 + (3- -1)^2) or sqrt 20.\n\nSo its equation is (x-4)^2 + (y+1)^2 = 20\n\nThe reason we know the center is at (4, -1) [at least how I did it] is by calling the center (a,b) and writing three different but equal applications of the distance formula, one from each known point to (a,b), then taking two pairs of these three distances, making them equal, and solving for a and b.
103447
In R^2 = (x-a)^2 + (y-b)^2, (a,b) are the (x,y) coordinates of the center of the circle.  If you literally want to draw the circle, set the distance between the compass points to R, put the center point on (a,b) and draw.  If you want to program a computer to draw it, you create a loop where theta (the angle) goes from 0 to 2pi (one full circle) in small steps.  Then at each step, turn on the pixel nearest to (a + R*cos(theta), b + R*sin(Theta)).
182934
You are given only Center (h,k) and radius r. Use the formula:\n(x - h)^2 + (y - k)^2 = r^2\nTransform this into:\nx^2 + y^2 + Ax + By + C = 0\nFor easier substitution.\n\nOr...\n\nWith the center (h,k) and radius r,\n\nPlot the points (h,k + r) (h,k - r) (h + r,k) and (h - r,k)\nThese points will be your guide to draw the circle!!
981000
the equation for the circle is ( x-h)^2 + ( y-k)^2 = r^2\nnotice the plus sign (but  in your question there is a minus sign)\nso this equation is a hyperbola.
833623
perpendicular distance s the shortest\nlet the pont be (x,y)\ncentre of the circle=(1,2)\nequation of the line joining (1,2)and (-2,-2)\n(y-2)/(-2-2)=(x-1)/(-2-1)\n-3(y-2)=-4(x-1)\n4x-3y+2=0\nsolve this with the equation of the circle\nto get the coordinates 'x' and'y'
568696
rare gem's answer is right..given the radius you'll just need to compute for the area using the formula right?\n\nArea=(radius^2)(pi)\n    = (5)(5)(pi)
971505
When graphing, the open circle indicates "less than" and "greater than", the closed circle indicates "less than or equal to" and "greater than or equal to".  In your case, you need a CLOSED circle at -1/2 and shade to the left since the numbers to the left of -1/2 are less in value.  The arrow placed at the end indicates that ALL numbers in that direction are less than or equal to -1/2.