Answer:

or 
Step-by-step explanation:
Given information is :
Two varieties of maple trees have been selected.
Let the first variety of trees be = x
Let the second colorful variety of trees be = y
One variety costs $75 per tree; 
The other more colorful variety costs $90 per tree; 
Given is - The tree budget must not exceed $70,000. This means the total cost of the trees should be less than or equal to 70000.
Thus, the equation forms:

Also given is - Citizens want more of the colorful $90 trees than the others if possible.
The equation will be :
or 