Line 180: |
Line 180: |
| =8-3<br> | | =8-3<br> |
| =5 | | =5 |
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| + | =Ex.no.9.11 /problem no.9= |
| + | The altitude of a triangle is 6cm greter than its base. If its area is 108cmsq .Find its base.<br> |
| + | Statement: Solving problem based on quadratic equations.<br> |
| + | *Interpretation of the problem:<br> * Converting data in to eqn.<br> *Knowledge about area of a triangle.<br>*knowledge of the formula of area of triangle.<br>*Methods of finding the roots of the eqn.<br> *Methods of finding the roots of the |
| + | *Different approches to solve the problem: <br>*Factorisation |
| + | *Using formula |
| + | *using graph |
| + | *Concept used:Forming the eqn. 216=x(x+6) |
| + | 216=x2+6x<br> |
| + | x2 +6x -216=0<br> |
| + | Substitution: x 2 +18x-12x -216=0<br> |
| + | Simplification: x(x+18)-12(x+18)=0<br> |
| + | (x+18)( x-12)=0<br> |
| + | (x+18)=0 (x-12)=0<br> |
| + | x=-18, x=12<br>. |
| + | # Base=12cm, <br> Altitude=x+6 |
| + | =12+6=18cm.<br> |
| + | '''Prior Knowledge''' -<br> |
| + | *Methods of solving the Eqn<br> |
| + | *Factorisation<br> |
| + | *Using Formula<br> |
| + | *Using Graph<br> |
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| = Project Ideas = | | = Project Ideas = |
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| = Math Fun = | | = Math Fun = |