36-4.5x+36=102-7.5x-60
72-4.5x=42-7.5x
72+3.5x=42
3.5x=-30
x=8.57
Point slope from would be 12x-y+26=0.
Black is the equation, 12x-y+26=0.
- Orange is <em>y-14=12(x+1)</em>
- Blue is <em>y-14=12(x-1)</em>
- Red is <em>y+14=12(x-1)</em>
- Green is <em>y-14=-12(x+1)</em>
Answer:
b
Step-by-step explanation:
Suppose:
C=cost
c=cost per kilo-watt hour
w=number of watts
h=number of hours
thus
C=kwhc
where:
k=constant of proportionality:
k=C/(whc)
but
C=15 when w=6000, h=10/60=1/6 hours, c=7.5 cents per kw/h
thus
k=15/(6000*1/6*7.5)
k=0.002
thus:
C=0.002(whc)
hence:
when
h=70*2=140=140/6=70/3 hours the cost will be:
C=0.002(6000*70/3*7.5)
C=2100 cents
C=$21
