solve v^2=u^2 +2as when

v=-30
u=20
a=10
and a is unknown

To solve for "a", you can rearrange the equation and substitute the given values:

v^2 = u^2 + 2as

(-30)^2 = (20)^2 + 2(a)(-30) [Substituting v=-30, u=20]

900 = 400 - 60a

Now, isolate the "a" term:

900 - 400 = -60a

500 = -60a

Finally, solve for "a":

a = 500 / -60

a ≈ -8.33

Therefore, when v = -30, u = 20, and a is unknown, the value of "a" that satisfies the equation v^2 = u^2 + 2as is approximately -8.33.