Question

1.Find equations for the lines through the point (a,b) that

Answer 1

1.

parellel的话 y = mx - am + b

perpendicular的话 y = -x/m + a/m + b

2.求点到直线的距离:D(x) = (8+4*6)/√(1²+6²)

3.

(a) P = kAv³

(b) 速度是原来的4倍 cross sectional area是一半,所以 P2 = k (A/2) (4v)³ = 32kAv³

所以答案是 by a factor of 32