1 inch = 400 miles The scale gives the relationship between the measurements of the drawing or model and the measurements of the real object.
Since 4>1, this represents exponential growth.
-4r-11=4r+21
Move 4r to the other side
Sign changes from +4r to -4r
-4r-4r-11=4r-4r+21
-4r-4r-11=21
-8r-11=21
Move -11 to the other side
Sign changes from -11 to +11
-8r-11+11=21+11
-8r=21+11
-8r=32
Divide both sides by -8
-8r/-8=32/-8
Answer: r=-4
When multiplying two powers that have the same base, you can add the exponents.
The answer is : 1:6 repeating
