Answer:
d
Step-by-step explanation:
Given y is directly proportional to x² then the equation relating them is
y = kx² ← k is the constant of proportion
To find k use the condition y =
when x =
, then
= k(
)² =
k ( multiply both sides by 8 )
1 = 2k ( divide both sides by 2 )
k = 
y =
x² ← equation of proportion
When y =
, then
=
x² ( multiply both sides by 2 )
9 = x² ( take the square root of both sides )
x = ±
= ± 3
with positive value x = 3 → d
Answer:-5
Step-by-step explanation:
2x+7-x+12=14
x+19=14
x=-5
Answer:
b
Step-by-step explanation:
centroid
x=(x1+x2+x3)/3=(0+3+0)/3=3/3=1
y=(y1+y2+y3)/3=(0+0-3)/3=-3/3=-1
centroid =(1,-1)
Answer:
240 cell phones
Step-by-step explanation:
=12×1500
=18000÷75
=240