Answer:
I think a or C
Step-by-step explanation:
Answer:
f(x) = -5/9 x + 5 1/9
Step-by-step explanation:
f(2)=4 and f(−7)=9 means the line pass through (2,4) and (- 7,9)
f(x) = mx + b
m = (y-y') / (x-x') = (9 - 4) / (- 7 - 2) = - 5/9
for (2,4) : b = f(x) - mx = y - mx = 4 - (- 5/9) x 2 = 4 + 10/9 = 46/9 = 5 1/9
f(x) = -5/9 x + 5 1/9
check for (-7, 9) f(-7) = (-5/9) * (-7) + 5 1/9 = 35/9 + 46/9 = 81/9 = 9
Presumably d meanst distance and t means time.
When t = 1, d = 2.5
When t = 3, d = 4
d = mt + b
2.5 = m + b [t = 1]
4.0 = 3m + b [t = 2]
1.5 = 2m [subtract]
m = .75 = slope
b = 1.75 = d-intercept
d = .75t + 1.75
d = 15/4 + 7/4 [t = 5]
d = 22/4 = 5.5 m from sensor
60c+80=287
Let c stand for the cost of one square foot. with 60 square feet you get 60c. then add 80 for the installation fee.
