Slope intercept form is: y=mx+b
So you take the first equation: 2x-3y=6 and you subtract the 2x from both sides and get: -3y= 2x+6
Then you take that equation: -3y= 2x+6 and divide -3 from both sides and get: y= -2/3x -2 
So the equation 2x-3y=6 in slope intercept from is 
y = -2/3x -2
Can you do the next one your self based on the one i did...? 
(Scroll and check ⬇️ )
Here ya go ;) 
5x + 2y = 3 okay same steps as above you want to get the x on the other side so you subtract the 5x from both sides and get:
2y = 5x + 3
Then you want to get the y by its self so you divide the 2 from both sides so you get:
y = 5/2x +2/3
Now idk if your allowed to leave it like that (based on your teacher's preferance really) but if not you can simplfy your fractions and get:
y = 2.5x + 0.66
( i would leave the 2/3 and just leave it as y = 2.5x + 2/3 ) but you do you and i hope that helped you :)
        
             
        
        
        
If its on a graph just look for the spot where the line meets the y and x-axis 
        
             
        
        
        
Answer:
The street light is 20 feet tall.
Step-by-step explanation:
This question depends on a proportion. Keep your height of the object in one ratio and the length of the shadow in the other.
25/x = 75/60      Notice the height of the structure is on the left. The length of the shadow is on the right. Cross multiply
75x =  60 * 25     Combine the right
75x = 1500          Divide by 75
x = 1500/75
x = 20
The street light is 20 feet tall.