Another question which is confusing.
The position of an object moving in a straight line is give by s=2t^2-3t, where is s in metres and t is the time in seconds the object has been in motion..
how long will it is take the object to move 6 meters?
I first used the simplfying rule but it did not work.. Then I used the vertex formula and I got a 2.5 from which I got a negative number..
Moreover then I used the quadratic formula and I got a 2.6 which I put in the formula of 2t^2-3t and I got a 5.7
Where am I going wrong?
The true answer is 2.6 seconds.
s=2t^2-3t
2t^2-3t-6=0
t= (3+-sqrt(9+48))/4=3/4 +-(sqrt57)/4
in my head t= .75+-7.5/4=.75+-about 1.8
= about 2.6seconds So recheck your quadratic formula solution
Aha, how silly of me!
My answer were absolutely correct, which was 2.6.. I don't know what urged me to go ahead and put it in the formula again..
Thank you for reconfirming my stupidity.
To find out how long it will take the object to move 6 meters, you need to set the equation s = 2t^2 - 3t equal to 6 and solve for t. Here's the correct approach to solving this problem:
1. Start with the equation:
2t^2 - 3t = 6
2. Rearrange the equation to bring it to standard quadratic form:
2t^2 - 3t - 6 = 0
3. Now, you can solve this quadratic equation using the quadratic formula:
t = (-b ± √(b^2 - 4ac)) / (2a)
where a = 2, b = -3, and c = -6.
4. Plug in the values into the formula:
t = (-(-3) ± √((-3)^2 - 4 * 2 * -6)) / (2 * 2)
Simplifying further:
t = (3 ± √(9 + 48)) / 4
t = (3 ± √57) / 4
5. Now, you have two possible values for t, but we need to choose the positive value since time cannot be negative. Therefore, we take the positive value:
t = (3 + √57) / 4
t ≈ 2.6 seconds
So, the correct answer is approximately 2.6 seconds. It seems like you made a calculation error in step 4, which led to the incorrect result of 5.7 seconds. Double-check your calculations, especially when simplifying the square root expression (√57).