Machu Picchu currently has about 18000 visitors daily. The area of Machu Picchu is about 13 km. Calculate the daily visitor density, or how crowded Machu Picchu is, in daily visitors per
square mile.

if y=4x then you will substitute 4x in for y in the second equation.

8x + 4x = 18 combine like terms

12x = 18 divide by 12 on both sides

x = 18/12 or 3/2

now replace x in the first equation with 3/2 to get

y = 4 3/2

y = 6

the answer is a

(3/2,6)

hope that .

brainliest is always apprectiated

130 degrees. i have no other way to explain