## Monday, September 13, 2010

### Summary of Linear Equations

• What we had learnt from today's maths lesson (for the first 3, let p & q the x-intercepts)
1. The roots of a parabola are the x-intercepts and right them in the proper way like (p,0)
2. To find the y-intercept of the parabola, the person must find the result without the x in it such as from equation (x-p)(x-q) and the result from equation without the x in it is pq so the y-intercept would be (0,pq).
3. To find the line of symmetry of the parabola, we must find the centre of the x-intercepts and the equations would be p+q/2.
4. The way to expand equations, let the integer in a bracket multiply with the equation in the other bracket. eg. (2-k)(4+k)= 2x4, 2xk= -k(8+2k)=-kx4, -kxk= 8+2k-4k-k square= 8-2k-k square
5. Equations needed to remember
• (a+b)square=a square + 2ab+ b square
• (a-b)square= a square - 2ab +b square
• (a+b)(a-b)= a square - b square
Note: (a+b) square is not equal to a square + b square

Question: There are U & n shaped parabola going upwards or downwards so is there such thing as a C shaped parabola?
If there is such thing, is it called parabola or anything else?