Given:
The graph of a quadratic function passes through the points (5,31) (3,11) (0,11).
To find:
The equation of the quadratic function.
Solution:
A quadratic function is defined as:
...(i)
It is passes through the point (0,11). So, substitute in (i).
Putting in (i), we get
...(ii)
The quadratic function passes through the point (5,31). So, substitute in (ii).
Divide both sides by 5.
...(iii)
The quadratic function passes through the point (3,11). So, substitute in (ii).
Divide both sides by 3.
...(iv)
Subtracting (iv) from (iii), we get
Putting in (iv), we get
Putting in (ii), we get
Therefore, the required quadratic equation is .
