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Which point on the graph of g(x)=(1/5)^x? HELPP

Which point on the graph of g(x)=(1/5)^x? HELPP-example-1
User Aggsol
by
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1 Answer

2 votes

Answer:

(-1,5) and
(3, (1)/(125)) are points on the graph

Explanation:

Given


g(x) = (1)/(5)^x

Required

Determine which point in on the graph

To get which of point A to D is on the graph, we have to plug in their values in the given expression using the format; (x,g(x))

A. (-1,5)

x = -1

Substitute -1 for x in
g(x) = (1)/(5)^x


g(x) = (1)/(5)^(-1)

Convert to index form


g(x) = 1/((1)/(5))

Change / to *


g(x) = 1*((5)/(1))


g(x) = 5

This satisfies (-1,5)

Hence, (-1,5) is on the graph

B. (1,0)

x = 1

Substitute 1 for x


g(x) = (1)/(5)^x


g(x) = (1)/(5)^1


g(x) = (1)/(5)

(1,0) is not on the graph because g(x) is not equal to 0

C.
(3, (1)/(125))

x = 3

Substitute 3 for x


g(x) = (1)/(5)^x


g(x) = (1)/(5)^3

Apply law of indices


g(x) = (1)/(5) * (1)/(5) * (1)/(5)


g(x) = (1)/(125)

This satisfies
(3, (1)/(125))

Hence,
(3, (1)/(125)) is on the graph

D.
(-2, (1)/(25))

x = -2

Substitute -2 for x


g(x) = (1)/(5)^x


g(x) = (1)/(5)^(-2)

Convert to index form


g(x) = 1/((1)/(5)^2)


g(x) = 1/((1)/(5)*(1)/(5))


g(x) = 1/((1)/(25))

Change / to *


g(x) = 1*((25)/(1))


g(x) = 25

This does not satisfy
(-2, (1)/(25))

Hence,
(-2, (1)/(25)) is not on the graph

User Raul Cuth
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4.7k points