SOLUTION: For each of the following curves, find the values of x for which y<0. a) y=2x^2 +4x +1 b) y=-2x^2+5x+3

Question 1130505: For each of the following curves, find the values of x for which y<0.
a) y=2x^2 +4x +1
b) y=-2x^2+5x+3

Answer by Boreal(15235) (Show Source): You can put this solution on YOUR website!
2x^2+4x+1<0
x=(1/4)(-4+/- sqrt (16-8) or (-1+/-.5 sqrt(2))
Numerically, this is between -1.707 and -0.293 or (-1-.5 sqrt (2), -1 +.5 sqrt(2)) ANSWER

-2x^2+5x+3=0 multiplying by -1, 2x^2-5x-3=0
factors into (2x+1)(x-3)=0, so x=-1/2 and x=3 are critical points.
x=-1 testing and y=-4, so to the left of x=-1/2 , y <0
in between use 0 and the function equals 3, so that part is greater than 0.
above 3, use 4 and the function equals -9, so that part is less than 0. Interval (-oo, -1/2) U (3, oo)

RELATED QUESTIONS
For which values of x do y^2=5x^2-4x and y=2x-3... (answered by lwsshak3)

1.Sketch the curves of the following functions (a) f(t)= 4t^2- 12t (b) f(x)= 4-2x-x^2... (answered by rothauserc)

Hi, i tried solving my assignments, please help me check if i did it right..Thanks in... (answered by Alan3354)

) Give the values of m and c for each straight line equation a) y = 2x + 3 (answered by solver91311)

For each of the following inequalities indicate whether the boundary line should be... (answered by vleith)

Find the points of intersection of the following pair of curves. y=4x^2+66x+283,... (answered by Cromlix)

How do you Find the slope and y-intercept of each equation? Then graph. 1.) y=x+2 (answered by checkley75)

Show all work. Be sure to answer both part A and B to the following questions. Part A, (answered by MathLover1)

if y = 2x +3 and x < 2 which of the following represents all the possible values for y ? (answered by Edwin McCravy)