Question

Sam is observing the velocity of a car at different times. After three hours, the velocity of the car is 51 km/h. After five hours, the velocity of the car is 59 km/h.

Write an equation in two variables in the standard form that can be used to describe the velocity of the car at different times. Show your work and define the variables used.

How can you graph the equation obtained in Part A for the first six hours?

Answer 1

@ganeshie8

Answer 2

@amistre64

Answer 3

you are given 2 points of reference, how do we create a line equation using 2 points?

Answer 4

plot the two points and connect them

Answer 5

thats how we graph them, thats not how we make an equation

Answer 6

ohh,

y = mx + b

Answer 7

or if we dont know the y intercept: just use point and slope

y = m(x-xo) + yo

Answer 8

xo,yo is either point of reference, so all we need to do is determine the slope between the points

Answer 9

(3, 51) and (5, 59)

m = y2 - y1/x2 - x1
m = 59 - 51/5 - 3
m = 8/2
m = 4

y = mx + b
y = 4x + b

(3,51) y = 4x + b
51 = 4(3) + b
51 = 12 + b
51 - 12 = 39
b = 39

(5,59) y = 4x + b
59 = 4(5) + b
59 = 20 + b
59 - 20 = 39
b = 39

y = 4x + 39

Answer 10

@amistre64 is this correct?

Answer 11

(3, 51) and
-(5, 59)
--------
-2,-8: slope is is good

now the equation is just: y = 4(x-3)+51 using the slope and the point (3,51)

Answer 12

in your case y = 51-12 = 41-2 = 39 is finne as well

Answer 13

b=, not y= had a typo

Answer 14

so, this gives us a linear model for the points of reference, and we can now guess at the solution for what was it, x=6?

Answer 15

y = 4(6) + 39
y = 24 + 39
y = 63

Answer 16

we can know graph the equation for x=0 thru x=6,

Answer 17

good: 0,39 and 6,63 are the end points for our graph

Answer 18

Thank you so much for your help, I really appreciate it. I had no idea what they were asking me to do, lol.

Answer 19

youre welcome