Question

Evaluate and Explain

3t(t+2)-3t^2 for t=19
and
Simplifiy
-(3a-2b)-3(-a-b)

Answer 1

1 ) 3 t ( t + 2 ) - 3 t² =
= 3 t² + 6 t - 3 t² = 6 t = 6 · 19 = 114

2 ) - ( 3 a - 2 b ) - 3 ( - a- b ) =
= - 3 a + 2 b + 3 a + 3 b = 5 b