Question

If d = p + 0.5at^2, which equation is solved for t?

Answer 1

@Michele_Laino

Answer 2

@pooja195

Answer 3

@mathmale

Answer 4

@Alex_Mattucci it says "which equation" then there must be answer choices ^_^

Answer 5

yeah...
forgot to put those in

Answer 6

First of, If my memory is not failing me (all that are watching please correct)... we subtract P from both sides

Answer 7

Second we would divide the result expression by 0.5a

Answer 8

Then finally we figure out the square root of both sides ^_^

Answer 9

A. Sqrt d-p-0.5/a
B. Sqrt d+p-0.5/a
C. Sqrt d+p/0.5a
D. Sqrt d-p/0.5a

Answer 10

Hope that helps c:

Answer 11

Oh so that would be D!

Answer 12

A. t=Sqrt d-p-0.5/a
B. t=Sqrt d+p-0.5/a
C. t=Sqrt d+p/0.5a
D. t=Sqrt d-p/0.5a

Answer 13

first step:
if I subtract \(p\) from both sides, I get:
\[d - p = p + \frac{1}{2}a{t^2} - p\]
please simplify

Answer 14

forgot the t= in those answers above

Answer 15

that would be d-p=1/2at^2

Answer 16

that's right!

Answer 17

second step:
if I multiply both sides by \(2/a\), I get:
\[\left( {d - p} \right)\frac{2}{a} = \frac{2}{a} \cdot \frac{a}{2}{t^2}\]
please simplify

Answer 18

d-p/0.5a=t^2

Answer 19

hint:
left side is: \[\left( {d - p} \right)\frac{2}{a}\]

right side:
what is:
\[\frac{2}{a} \cdot \frac{a}{2} = ...?\]

Answer 20

i don't know

Answer 21

hint:

Answer 22

oh so they cancel out

Answer 23

yes! so, what do you get?

Answer 24

t^2

Answer 25

on the right side

Answer 26

that's right!
so we can write this:
\[{t^2} = \left( {d - p} \right)\frac{2}{a}\]

Answer 27

finally, I take the square root of both sides, so I can write:
\[\huge \sqrt {{t^2}} = \sqrt {\left( {d - p} \right)\frac{2}{a}} \]
please simplify the left side

Answer 28

t

Answer 29

that's right!
so we get:
\[\huge t = \sqrt {\left( {d - p} \right)\frac{2}{a}} \]
more precisely, we have:
\[\Large \sqrt {{t^2}} = \pm t\]
since time is positive, then we take the positive square root

Answer 30

ok

Answer 31

:)

Answer 32

so now what?

Answer 33

we have finished, you got the right answer:
\[t = \sqrt {\left( {d - p} \right)\frac{2}{a}} \]

Answer 34

but those are not a, b, c, or d

Answer 35

we can write the right side as below:
\[\Large t = \sqrt {\left( {d - p} \right)\frac{2}{a}} = \sqrt {\frac{{d - p}}{{a/2}}} = \sqrt {\frac{{d - p}}{{0.5a}}} \]
since \(1/2=0.5\)

Answer 36

oh ok, that makes more sense!

Answer 37

:)

Answer 38

so, what is the right option?

Answer 39

Thank you so much for all your help! The answer is D!

Answer 40

that's right!