The equation is bigger than the window.

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<html lang="en-US"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width,initial-scale=1"><title>The equation is bigger than the window.</title><style>:root{--paper:#f5f7fb;--ink:#23344d;--accent:#375a91;--line:#c7d3e5;--panel:#fff;--soft:#e8eef8}*{box-sizing:border-box}:root{color-scheme:light}body{margin:0;background:var(--paper);color:var(--ink);font:17px/1.65 system-ui,-apple-system,"Segoe UI",sans-serif}main{max-width:960px;margin:auto;padding:28px 24px 54px}.strap{font-weight:750;letter-spacing:.07em;font-size:16px;color:var(--accent)}header{padding:20px 0 24px;border-top:7px solid var(--accent);border-bottom:2px solid var(--line);margin-bottom:24px}h1{font:700 clamp(30px,5vw,45px)/1.2 Georgia,serif;margin:10px 0 18px;max-width:780px}h2{font:700 25px/1.35 Georgia,serif;margin:0 0 16px}h3{font-size:19px;margin:18px 0 10px}p{margin:12px 0}section{margin:24px 0;padding:22px;background:var(--panel);border:1px solid var(--line);border-radius:8px;min-width:0}.plain section{border-radius:0;border-width:0 0 2px;padding:24px 0;background:transparent}.studio header{border-top-style:double;border-top-width:10px}.studio section{box-shadow:5px 5px 0 var(--line)}.board section{border-top:5px solid var(--accent)}.metric{font-size:clamp(26px,5vw,38px);font-weight:750;line-height:1.3}.grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:20px}.three{grid-template-columns:repeat(3,minmax(0,1fr))}.cell{padding:16px;background:var(--panel);border-left:4px solid var(--accent);min-width:0}.choices,.toolbar{display:flex;flex-wrap:wrap;gap:10px;margin:12px 0 18px}button,input,textarea{font:inherit}button{padding:11px 16px;min-height:46px;border:1px solid var(--accent);border-radius:6px;background:var(--panel);color:var(--accent);cursor:pointer;max-width:100%;line-height:1.4}button:hover{box-shadow:0 0 0 2px var(--line)}button[aria-pressed=true],button.primary{background:var(--accent);color:#fff}button:focus-visible,input:focus-visible,textarea:focus-visible{outline:3px solid #a25718;outline-offset:3px}label,legend{font-weight:650;display:block;margin:12px 0 7px}fieldset{border:0;padding:0;margin:16px 0;min-width:0}input,textarea{border:1px solid #6a7c7d;background:#fff;color:#182f32;padding:11px;width:100%;min-width:0;border-radius:5px}textarea{resize:vertical}.feedback{padding:16px;border-left:4px solid var(--accent);background:var(--soft);margin:18px 0;white-space:pre-line;overflow-wrap:anywhere}.note{border-left:4px solid var(--accent);padding:12px 16px;background:var(--soft)}table{width:100%;border-collapse:collapse;table-layout:fixed;font-size:16px}th,td{text-align:left;vertical-align:top;padding:11px 8px;border-bottom:1px solid var(--line);overflow-wrap:anywhere}th{background:var(--soft)}svg{display:block;width:100%;height:auto;max-width:540px;margin:16px auto;background:#fff}svg text{font:24px system-ui;fill:var(--ink)}footer{border-top:2px solid var(--line);margin-top:30px;padding-top:18px;font-size:16px}[hidden]{display:none!important}.sentence{font:26px/1.7 Georgia,serif;padding:16px;background:var(--soft)}.map-node{border:2px solid var(--accent);padding:16px;text-align:center;font-size:23px;background:var(--panel);max-width:460px;margin:auto}.map-link{text-align:center;padding:10px;font-weight:700}.lane{padding:18px;border:2px dashed var(--line)}@media(max-width:640px){main{padding:20px 16px 40px}.grid,.three{grid-template-columns:1fr}section{padding:18px 14px}.studio section{box-shadow:3px 3px 0 var(--line)}th,td{padding:9px 5px}}</style></head><body class=""><main><header><div class="strap">ORIGINAL WORKED EXAMPLE</div><h1>The equation is bigger than the window.</h1><p>Integer m and b from −10 to 10. View x and y from −5 to 5; the line continues beyond the frame.</p></header><div class="grid"><div><label for="slope">Slope m</label><input id="slope" type="text" aria-label="Slope m" value="3" autocomplete="off"><label for="intercept">Intercept b</label><input id="intercept" type="text" aria-label="Intercept b" value="-2" autocomplete="off"><div class="toolbar"><button type="button" id="plot" >Plot line</button><button type="button" id="reset" >Reset</button></div><div id="equation" class="feedback" role="status" aria-live="polite">Not checked yet.</div><div id="line-note" class="feedback" role="status" aria-live="polite">Not checked yet.</div></div><div id="graph" aria-label="Current line graph"></div></div><section ><h2>Complete coordinate table</h2><div id="points" class="feedback" role="status" aria-live="polite">Not checked yet.</div></section><p class="note">A valid point can lie outside the window. For the default line, (3,7) is valid but outside; (1,2) is visible but fails substitution. This input form does not represent vertical x = c.</p><footer>Local review only. Entries and changes stay in this open page; reload restores the example. Keep actual records in the required native document or workflow.</footer></main><script>
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function clear(){put('equation','Inputs changed. Plot the current pair.');put('line-note','');put('points','');$('graph').innerHTML='';}function plot(){try{const m=number('slope',-10,10,true),b=number('intercept',-10,10,true);put('equation','y = '+m+'x '+(b<0?'− '+Math.abs(b):'+ '+b)+'; intercept (0,'+b+'). Rise '+m+' / run 1.');const xs=[-1,0,1,2,3];put('points',xs.map(x=>{const y=m*x+b;return '('+x+','+y+'): '+m+' × '+x+' + '+b+' = '+y+' — '+(Math.abs(y)<=5?'inside window':'outside window, valid point');}).join('\n'));const visible=m!==0||Math.abs(b)<=5;put('line-note',visible?(m===0?'Horizontal line y = '+b+'. ':'')+'Equal x/y units. Line continues beyond the view.':'Valid line; no visible segment in this window.');let svg='<svg viewBox="0 0 400 400" role="img" aria-label="Line graph with equal unit spacing"><title>Line '+m+'x plus '+b+', window minus five to five</title><defs><clipPath id="plot-clip"><rect x="50" y="50" width="300" height="300"/></clipPath></defs>';for(let k=-5;k<=5;k++){const t=200+k*30;svg+='<path d="M50 '+t+'H350 M'+t+' 50V350" stroke="#d6dfea"/>';if(k%2!==0||k===0)svg+='<text x="'+t+'" y="375" text-anchor="middle">'+k+'</text><text x="20" y="'+(206-k*30)+'">'+k+'</text>';}svg+='<path d="M50 200H350 M200 50V350" stroke="#23344d" stroke-width="2"/><text x="365" y="207">x</text><text x="205" y="30">y</text><g clip-path="url(#plot-clip)"><path d="M50 '+(200-30*(m*(-5)+b))+' L350 '+(200-30*(m*5+b))+'" stroke="#375a91" stroke-width="3"/>';for(const x of xs){const y=m*x+b;if(Math.abs(y)<=5)svg+='<circle cx="'+(200+30*x)+'" cy="'+(200-30*y)+'" r="5" fill="#8b4513"/>';}svg+='</g></svg>';$('graph').innerHTML=svg;}catch(e){put('equation',e.message);put('points','');put('line-note','');$('graph').innerHTML='';}}edit(['slope','intercept'],clear);on('plot',plot);on('reset',()=>{$('slope').value='3';$('intercept').value='-2';plot();});plot();
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