Help PLzzz!!
A fountain on a lake sprays water in a parabolic arch modeled by the equation y = -0.3x2 + 3x. A beam of light modeled by the equation
-2x + 5.5y = 19.5 passes through the fountain to create a rainbow effect. If the beam cuts the water spray at points A and B, such that point B is at a higher level than point A, what distance from the ground level is point A?
1.66 units
4.15 units
5.44 units
6.14 units
7.13 units

Question

Help PLzzz!!
A fountain on a lake sprays water in a parabolic arch modeled by the equation y = -0.3x2 + 3x. A beam of light modeled by the equation
-2x + 5.5y = 19.5 passes through the fountain to create a rainbow effect. If the beam cuts the water spray at points A and B, such that point B is at a higher level than point A, what distance from the ground level is point A?
1.66 units
4.15 units
5.44 units
6.14 units
7.13 units

welshfella · Answer

to find the intersecting point  solve the system of 2 equations given.

wibrahim · Answer

okay

welshfella · Answer

y = -0.3x^2 + 3x

-2x + 5.5y = 19.5


you need to find the highest  y value 

from second equation  x =  (5.5y - 19.5) / 2 = 2.75y - 9.75

plug this value  for x into the first equation and solve for y.

wibrahim · Answer

thank uu11

welshfella · Answer

the algebra is a bit messy though

welshfella · Answer

if you have a graphical calculator  i'd use it