Answer:
9
Step-by-step explanation:
X + 2x + x + 10 = 90
4x = 80
x = 20
Answer:
Step-by-step explanation:

Answer:
y($) = 405- 20x
Step-by-step explanation:
Number of short driveways = x
Number of long driveways = 9-x
Fee per long driveway = $45
Fee per short driveway= $25
Total amount = y
y ($) = 25x + 45 (9-x)
= 25x + 405 -45x
= 405- 20x
Answer:
x = 3
Step-by-step explanation:
8z = 2x + 18
6x = 18
x = 3