PHYSICS-PULLEY and ANGLE PROBLEM (have answers need help understanding)

Question

A pulley has an initial angular speed of 2.50 rad/s and a constant angular acceleration of 1.40 rad/s^2. Through what angle does the pulley turn in 7.00 s? (answer: 51.8 rad)

Answer 1

θ_final - θ_initial = ωt + 1/2 αt²

Where \theta is the angle, \omega the initial angular speed, \alpha the angular acceleration, t the time.

Plugging in the numbers gives you 51.8 rad.

Answer 2

θ= w₀ t + 1/2 (α*t²)

plug in w₀ = 2.5

t= 7.0

α = 1.40

get θ in radian

θ= 2.5*7 +0..5*1.4*7*7 =51.8 radian