Question

For how many days is the total cost $300? ___days Initial Value 8 Rate of Change 15

Answer 1

• b=initial value=8
• m=rate if change(Slope)=15

Equate

$\\ \sf\longmapsto y=mx+b$

$\\ \sf\longmapsto 300=15x+8$

$\\ \sf\longmapsto 300-8=15x$

$\\ \sf\longmapsto 292=15x$

$\\ \sf\longmapsto x=\dfrac{292}{15}$

$\\ \sf\longmapsto x=19.5$

Answer 2

Answer:

• ≈ 19.5 days

Step-by-step explanation:

• Initial Value b = 8
• Rate of Change  m = 15

Equation of the line:

• y = 15x + 8

Find x when y = 300:

• 15x + 8 = 300
• 15x = 300 - 8
• 15x = 292
• x = 292/15
• x ≈ 19.5 days