The graph represents the function where electricity usage in kilowatts per hour of a clock radio varies directly with the number of days it is plugged into the wall current. A coordinate grid showing Clock Radio Electricity Usage, with Days Connected to Current on the x-axis and Electricity Usage in kilowatt hours on the y-axis with a line starting at (0, 0) and passing through (2, 0.5) and (6, 1.5).
Which is a reasonable estimate of the constant of variation?

0.25 kWh per day
0.50 kWh per day
2.40 kWh per day
4.00 kWh per day

3.4 pizzas

step-by-step explanation:

given is a scatter plot showing number of pizzas sold during weeks for different issues of coupon

y represents number of pizzas sold and x number of coupons issued

y is marked verticaly and x horizontally

the trend line is given as

y =3.4x+43

this says that even when no coupon is issued pizzas sold will be 43

and rate of change of pizza sold for 1 unit of coupon = slope = 3.4

i.e. when x increases by 1 unit y increases by 3.4 units

hence for each additional coupon issued 3.4 pizzas more will be sold

-14 is the answer

hope this : ))