Space geometry

1003188906

Level: 
A
Let there be planes α, β, γ and δ defined by their general equations: α:23x4y+6z83=0;β:x2y+3z4=0;γ:2x12y+18z4=0;δ:x6y+9z4=0. Out of the following statements, select the one that is not true.
αδαδ
Planes β and δ are intersecting.
γδγδ
Planes α and β are intersecting.
α=δ

1103188706

Level: 
A
We are given points A=[2;4;0] and B=[4;7;6]. Find parametric equations of a line q, which is the orthogonal projection of the line AB into the coordinate plane xy.
p:x=4+2t,y=7+3t,z=0; tR
p:x=2+4t,y=4+7t,z=6t; tR
p:x=4+2t,y=7+3t,z=6; tR
p:x=22t,y=43t,z=6t; tR