Solution: from the meaning of the question:

-k+6=2

k=4

Replace y=kx+b with k=4:

12+b= 1

∴b=- 1 1

3.2

Solution: Equations:

{x+(y-28)=224

{x=2y

Solve the equation:

{x= 168

{y=84

A: The height of the actor is 168cm, and the length of stilts is 84cm.

3.5

Solution: (1) Settings: Each skilled worker can install X electric cars every day, and new workers can install Y electric cars every month.

Equations:

{x+2y=8

{2x+3y= 14

Solution:

{x=4

{y=2

A: Every skilled worker can install four electric cars every day, and new workers can install two electric cars every month.

(2) Set up a factory with m skilled workers.

De: 12(4m+2n)=240。

Deformation: 2m+n= 10.

∫0 < n < 10, and even.

D: When n=2, so m=4.

When n=4, so m=3.

When n=6, so m=2.

When n=8, so m= 1.

A: There are four kinds, two new workers and four skilled workers.

4 new employees and 3 skilled workers;

6 new employees and 2 skilled workers;

8 new employees, skilled workers 1 person.

No points, and so on.