Could you guys check my answers?
1. Graph the function and identify the domaine and range. y=-1.5^2
Domain; (-,+)
Range; (-,0) ( my answers.)
2.How is the graph of y=-2x^2-5 different from the graph of y=-2x^2
It is shifted units up
it is shifted 5 units down <---
It is shifted 5 units left
It is shifted 5 units right.
3. A model rocket is launched from a roof into a large field. The path of the rocket can be modeled by the equation y=-0.04x^2+8.3x+4.3, where x is the horizontal distance, in meters from the starting point on the roof and y is the height in meters,of the rocket above the ground. How far horizontally from its starting point will the rocket land? Round your answer yo the nearest hundredth meter.
208.02 m<-----
416.03 m
0.52 m
208. 19 m
4.Landon is standing in a hole that is 6.5 m deep. he throws a rock, and it goes up into the air, out of the hole, and then lands on the ground above. The path of the rock can be modeled by the equation y=-0.05x^2+4.5x-6.5, where x is the horizontal distance of the rock, in meters, from landon and y is the height, in meters, of the rock above the ground. How far horizontally from landon will the rock land? Round your answer to the nearest hundredth of a meter.
a. 18.07 m <----
b. 35.96 m
c. 9.04 m
d. 71.93 m
5. How many real number solutions does the equation have? -7x^2+6x+3=0
one solution
two solution <---
No solution
infintely many solutions
6. How many real number solutions does the equation have? y=2x^2-20x+50
one solution <---
Two solutions
no solutions
infinetely solutions
7. Graph the set of points, which model is most appropriate for the set. (-6,0) (-4,2) (-3,3) (2,8)
Linear +
quadratic +
Linear-
Quadtratic - <---
9. y=x^2+3x-4
y=2x+2
(-3,6) and(2,-4)
(-3,-4) and (2,6)
(-3,-4) and (-2,-2) <----
No solution
10. y=x^2+8x+2
y=7x+4
(-2,-10) and (1,11) <----
(2,10) and (-1,-11)
(-2,-34) and (1,11)
11. If an object is dropped from a heigh of 144ft, the function h(t)=-6t^2+144 gives the heigh of the object after t second. when will the ball hit the ground?
1.5 s
3 s <--
6 s
9 s
12.A ball is thrown into the air with an upward velocity of 28 ft/s. its height in feet after t seconds is given by the function h=-16t+28+7. how long does it take the ball to reach its maximum height? What is the balls maximum height? Round to the nearest hundredth.
Reaches a maximum height of 7 feet after 1.75 seconds
Reaches a maximum height of 43.75 feet after 0.88 seconds
Reaches a maximum height of 17.5 feet after 0.88 seconds
Reaches a maximum height of 19.25 feet after 0.88 seconds <---
13. A catapult launches a boulder with an upwark velocity pf 184 feet per second. the heigh of the boulder in feet after t seconds is given by the function h(t)=-16t^2+184t+20. how long does it take the boulder to reach its maximum height? What is the boulders maximum height? Round to the nearest hundredth.
Reaches a maximum height of 11.6 feet after 5.75
Reaches a maximum height of 549 feet after 11.5 seconds
Reaches a maximum height of 549 feet after 5.75 seconds
Reaches a maximum height of 23.2 feet after 11.6 seconds. <----
14. Use the graph of (x) to find the solutions to the equation f(x)=0
Two solutions: x=-4, 7 <----
Two solutions: x=4,-7
One solution: x=28
No solutions.
15.
16.Solve the equation using the zero product property. (2x-4)(2x-1)=0
2, -1/2
2, 1/2 <----
-2, 2
-2, 1/2
18. A community group is planning the expansion of a square flower garden in a city park. If each side of the original garden is increased by 3 meters, the new total area of the garden will be 225 square meters. Find the length of each side of the original garden.
15 m
3 m
12 m <----
√12 m
19. What is the value of c so that y=x^2+15x+c is a perfect square trinomial?
30<----
15/2
15/4
225/4
20.Solve the equation by completeing the square. Round to the neareset tenth. x^2+8x=10
1.1, 9.1 <----
1.1, -9.1
-1.1, 9.1
-1.1, -9.1
21.Solve the equation by completeing the square. x^2+9x-14=0
10.35, 1.35<----
10.35, -1.35
-10,35, -1.35
-10.35, 1.35
22. Use the quadratic formula to solve the equation. If necessary, round to the nearest hundredth. x^2-12=-4x
6,2
6,-2
-6,2 <---
-6, -2
#4. I get 88.5 meters. Typo in the formula?
#7 y=x+6
#9 (-3,-4) and (2,6)
#13 Reaches a maximum height of 549 feet after 5.75 seconds
#14 no idea, since no graph here
#19 225/4
#20 1.1, -9.1
#21 -10.35, 1.35
The others look good (despite a few typos in the problems)
Your answer for #18 is correct.
1. Domain: (-∞, +∞) Range: (-∞, 0) (Correct)
2. How is the graph of y=-2x^2-5 different from the graph of y=-2x^2?
It is shifted 5 units down (Correct)
3. How far horizontally from its starting point will the rocket land? Round your answer to the nearest hundredth meter.
208.02 m (Correct)
4. How far horizontally from landon will the rock land? Round your answer to the nearest hundredth of a meter.
a. 18.07 m (Correct)
5. How many real number solutions does the equation -7x^2+6x+3=0 have?
Two solutions (Correct)
6. How many real number solutions does the equation y=2x^2-20x+50 have?
One solution (Correct)
7. Graph the set of points: (-6,0) (-4,2) (-3,3) (2,8).
Quadratic (+) - (Correct)
9. What are the solutions to the system of equations: y=x^2+3x-4, y=2x+2?
(-3,-4) and (-2,-2) (Correct)
10. What are the solutions to the system of equations: y=x^2+8x+2, y=7x+4?
(-2,-10) and (1,11) (Correct)
11. When will the ball hit the ground if its height is given by the function h(t)=-6t^2+144?
t = 3 s (Correct)
12. How long does it take the ball to reach its maximum height? What is the maximum height?
0.88 seconds, 19.25 feet (Correct)
13. How long does it take the boulder to reach its maximum height? What is the maximum height?
5.75 seconds, 549 feet (Correct)
14. Use the graph of f(x) to find the solutions to the equation f(x) = 0.
Two solutions: x=-4, 7 (Correct)
16. Solve the equation using the zero product property: (2x-4)(2x-1) = 0.
2, 1/2 (Correct)
18. Find the length of each side of the original garden if each side of the garden is increased by 3 meters and the new total area is 225 square meters.
12 m (Correct)
19. What is the value of c so that y=x^2+15x+c is a perfect square trinomial?
30 (Correct)
20. Solve the equation by completing the square: x^2 + 8x = 10.
1.1, -9.1 (Correct)
21. Solve the equation by completing the square: x^2 + 9x - 14 = 0.
10.35, -1.35 (Correct)
22. Use the quadratic formula to solve the equation: x^2 - 12 = -4x.
-6, 2 (Correct)