Answer:
40%
Step-by-step explanation:
20/50 = 40/100 = 40%
4x+12/x^2+9
Perimeter
x+3+x+3+x+3+x+3
Area
(x+3)(x+3)
180
for 40 to be equal to 80 in percentages, the number has to be duplicated
16n^2-25=0
16n^2=25
n^2=25/16
n=+-5/4
to replace 2x we need +6x-4x