Question 1028260
When a ball is served, consider the trajectory of ball modelled by equation y=-x^2/8 + 9x/8 +5/4.
Find the height of the ball when it is 3m horizontally from where served.
 (Y represents height of ball in metres above ground and x represents horizontal distance from when ball was struck).
{{{y=-x^2/8 + (9x)/8 + 5/4}}}
find y when x=3
{{{y=-3^2/8 + (9*3)/8 + 5/4}}} 
{{{y=-9/8 + 27/8 + 5/4}}}
{{{y= 18/8 + 5/4}}}
{{{y= 9/4 + 5/4}}}
{{{y= 14/4}}}
y = 3.5 meters is the height