Question

Help!

Steven recorded the growth of a plant over 10 weeks for his science project. He made a graph that shows how much the plant grew each week. The plant was 2 in. tall when Steven started his project. At week 5, the plant was 8 in. tall.

Which equation represents Steven’s situation, where x is the number of weeks and y is the height of the plant?

a. y=5/6x+2

b. y=5/8x+2

c. =8/5x+2

d. y=6/5x+2

Answer 1

D

Explanation:

take two points from the graph to find the slope

(0,2) and (10,14)

m=(y2-y1)/(x2-x1)

m=(14-2)/(10-0)

m=12/10

m=6/5

now take only one point from the graph to make a graph equation

(0,2) let us use this

m=(y2-y)/(x2-x)

m=(2-y)/(0-x)

m=(2-y)/(-x)

6/5=(2-y)/(-x)........... m=6/5

-x6/5=2-y

(-x6/5)-2=-y

-(-x6/5)(-2)=-(-y).....multiplying both sides by negative to make y positive

Y=x6/5-2

Answer 2

d. y=6/5x+2 -- correct choice