The graph of an exponential model in the form y = a ⋅ bx passes through the points (2, 50) and (3, 250). Which point is also on the graph?
A. (0, 5) B. (1, 10) C. (4, 450) D. (5, 650)

Respuesta :

Answer:

We choose B. (1, 10)

Step-by-step explanation:

Given the exponential model in the form y = a[tex]b^{x}[/tex]

  • passes through the points (2, 50)

<=> 50 = a[tex]b^{2}[/tex]  

<=> a = [tex]\frac{50}{b^{2} }[/tex] (1)

  • passes through the points  (3, 250)

<=> 250 = a[tex]b^{3}[/tex] (2)

Substitute (1) into (2) we have:

250 =  [tex]\frac{50}{b^{2} }[/tex][tex]b^{3}[/tex]

<=> 50b = 250

<=> b = 5

=> a = [tex]\frac{50}{5^{2} }[/tex] = 2

Hence, our exponential model is: y =2* [tex]5^{x}[/tex]

Let analyse all possible answer:

A. (0, 5) we have: y =2*  [tex]5^{0} =2[/tex] ≠ 5 so it is wrong

B. (1, 10) we have: y = 2* [tex]5^{1} =10[/tex] so it is true

C. (4, 450) we have: y = 2*[tex]5^{4} =1250[/tex] ≠ 450 so it is wrong

D. (5, 650)  we have: y = 2*[tex]5^{5} =6250[/tex] ≠ 650 so it is wrong

Hence we choose B. (1, 10)