Let
A(4,5) B(8,7) C(12,9) D(16,11)
1) Find the slope AB
m=(y2-y1)/(x2-x1)
m=(7-5)/(8-4)=0.5
2) Find the slope BC
m=(9-7)/(12-8)=0.5
3) Find the slope CD
m=(11-9)/(16-12)=0.5
The points represent a linear function
so
<u>Find the equation of the line with m=0.5 and the point A(4,5)</u>
we know that
y-y1=m*(x-x1)
y-5=0.5*(x-4)
y=0.5*x-2+5
y=0.5*x+3
therefore
<u>the answer is</u>
The equation is equal to y=0.5*x+3
The original number is 72
(18+x)/6 = 1+14
1/6x + 3 = 1 + 14 (Distribute)
1/6x + 3 = (1+14) (Combine Like Terms)
1/6x + 3 = 15
- 3 = -3 (Subtract 3 From Both Sides)
1/6x = 12
(1/6x)*6 = 12 * 6 (Multiply Both Sides By 6)
x = 72
100*2.2=220
80*2=176
220+176=396
So the two trains will take 2.2 hours so that they are 396 miles apart.
No, because the 9 pounds would cost 22.5, and that is 5 cents more than he has
