C=number of acres of corn
w=number of acres of wheat
total is 180 acres
c+w=180
wants to plant 3 times as many corn as wheat
c=3w
subsitute 3w for c in other
c+w=180
3w+w=180
4w=180
divide boh sides by 4
w=45
sub back
c=3w
c=3(45)
c=135
135 acres of corn and 45 acres of wheat
Y = 6/x does not show a direct variabtion
Answer
B. y = 6/x
Answer:
number of students in a van = 8
number of students in a minibus = 22
Step-by-step explanation:
Let
x = number of students in a van
y = number of students in a minibus
8x + 8y = 240 (1)
4x + y = 54 (2)
Multiply (2) by 8 to eliminate y
4x + y = 54 ×8
32x + 8y = 432 (3)
8x + 8y = 240 (1)
32x + 8y = 432 (3)
Subtract (1) from (3)
32x - 8x = 432 - 240
24x = 192
Divide both sides by 24
x = 192 / 24
= 8
x = 8 students
Substitute x = 8 into (2)
4x + y = 54
4(8) + y = 54
32 + y = 54
y = 54 - 32
= 22
y = 22 students
number of students in a van = 8
number of students in a minibus = 22