Respuesta :
It takes half a day for the bacteria to reach 243 million. The linear equation is solved for x= 0.5 or x=1/2.
Step-by-step explanation:
The given linear function is [tex]y= 9^{5x}[/tex] .
where,
- 'y' represents the size of bacteria in millions.
- 'x' represents the number of days to reach the size.
To find the number of days to reach the size of 243 million :
- The linear equation must be solved for y,
- It is given that the size of bacteria, y= 243.
Substitute y=243 in the linear equation [tex]y= 9^{5x}[/tex] to get the number of days x.
⇒ 243 = [tex]9^{5x[/tex]
- To find x, bring the base number as 9 in both sides to equal the exponents.
- For that, the number 243 must be split into 9×9×3 = 243
- Again bringing the base number as 3 in both sided to equate the exponents.
⇒ 243 can also be written as [tex]3^{5}[/tex]
⇒ [tex]3^{5}[/tex] = [tex]9^{5x[/tex]
⇒ [tex]3^{5}[/tex] = [tex]3^{10x[/tex]
⇒ The powers in both sides are 5 and 10x . The bases in both sides are same.
⇒ Comparing the power on both sides to solve for x value.
⇒ 10x = 5
⇒ x = 5/10
x= 1/2
x= 0.5
It takes half a day for the bacteria to reach 243 million