var my={} function areacalcMain(){my.version='0.76';w=440;h=490;var s='';s+='
';shapes=[{name:"Triangle",img:"triangle2.gif",formula:"½b × h",sub:"½ × #0 × #1",vals:[["b",55,77],["h",102,26]]},{name:"Circle",img:"circle.gif",formula:"π × r²",sub:"π × #0²",vals:[["r",90,31]]},{name:"Sector",img:"sector.gif",formula:"½r²θ",sub:"½ × #0² × #1",vals:[["r",90,54],["angle",-68,65,"θ"],["radq",-84,90]]},{name:"Ellipse",img:"ellipse.gif",formula:"πab",sub:"π × #0 × #1",vals:[["a",95,15],["b",-80,64]]},{name:"Square",img:"squar2.gif",formula:"a²",sub:"#0²",vals:[["a",100,35]]},{name:"Rectangle",img:"rectangle.gif",formula:"w × h",sub:"#0 × #1",vals:[["w",55,72],["h",100,28]]},{name:"Parallelogram",img:"parallel.gif",formula:"b × h",sub:"#0 × #1",vals:[["b",47,73],["h",100,32]]},{name:"Trapezoid",img:"trap.gif",formula:"½(a+b) × h",sub:"½(#0+#1) × #2",vals:[["a",70,0],["b",55,75],["h",102,36]]}];for(var i=0;i';s+='';s+='
';} s+='
';s+='
';s+='
';s+='
';s+='';s+='
© 2018 MathsIsFun.com v'+my.version+'
';s+='';document.write(s);go('area0');} function go(id){for(var i=0;i';var vals=shape.vals;for(var i=0;i';s+='radian';s+='degree';s+='' radQChg(0)}else{s+='';}} document.getElementById('entry').innerHTML=s;my.radQ=true valChg(0);} function radQChg(n){my.radQ=(n==0) console.log("radQChg="+my.radQ+','+n);valChg(0)} function valChg(n){var shapeName=shape.name;console.log("valChg="+shapeName+','+n);var formula=shape.formula var sub=shape.sub var area=0;switch(shapeName){case "Triangle":area=getVal(0)*getVal(1)/2;break;case "Circle":area=Math.PI*Math.pow(getVal(0),2);break;case "Sector":area=Math.pow(getVal(0),2)*getVal(1)/2;if(my.radQ){}else{formula+=" × (π/180)" sub+=" × (π/180)" area*=Math.PI/180.} break;case "Ellipse":area=Math.PI*getVal(0)*getVal(1);break;case "Square":area=Math.pow(getVal(0),2);break;case "Rectangle":area=getVal(0)*getVal(1);break;case "Parallelogram":area=getVal(0)*getVal(1);break;case "Trapezoid":area=(1/2)*(getVal(0)+getVal(1))*getVal(2);break;default:} var answer="";answer+="Area = "+formula var s=sub var vals=shape.vals for(var i=0;i0&&s.indexOf('e')<0){s=s.replace(/0+$/,'');} if(s.charAt(s.length-1)=='.'){s=s.substr(0,s.length-1);} return s;} function isNumeric(n){return!isNaN(parseFloat(n))&&isFinite(n);} function toggleBtn(btn,onq){if(onq){document.getElementById(btn).classList.add("yy");document.getElementById(btn).classList.remove("hi");}else{document.getElementById(btn).classList.add("hi");document.getElementById(btn).classList.remove("yy");}}