Basic Definite Integrals Question... How to solve... AP Calc Help

A particle starts at x=0 and moves along the x-axis with velocity v(t)=5 for time t>/=0. Where is the particle at t=4?

Please explain how to solve. I know you have to do RAM, but I keep getting an answer of 18 when the correct answer is 20.

Thanks!

Integrate 5 to get 5t from t = 4 to t = 0.
5(4) - 5(0) = 20
Starting positon + 20 = 0+ 20 = 20

Jen

v(t) = 5 for t ≥ 0, so the particle's velocity is constant over the measured interval.

The question asks where the particle is at time t = 4, which would be expressed by the integral
∫₀⁴ 5 dt
[5t]₀⁴
5∙4 - 5∙0
20

If v(t)= 5, then x(t)= 5t+C

Since x(0)=0, then C= 0

X(t)= 5t

X(4)= 5(4)= 20

Hoping this helps!