Answer: -35, -135, -235, -335, -435
Step-by-step explanation
The idea is to plug n = 1 through n = 5 into the equation to find the first five terms. The scratch work is shown below.
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Plug in the value n = 1
an = 65-100n
a1 = 65-100*1
a1 = 65-100
a1 = -35
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Plug in the value n = 2
an = 65-100n
a2 = 65-100*2
a2 = 65-200
a2 = -135
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Plug in the value n = 3
an = 65-100n
a3 = 65-100*3
a3 = 65-300
a3 = -235
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Plug in the value n = 4
an = 65-100n
a4 = 65-100*4
a4 = 65-400
a4 = -335
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Plug in the value n = 5
an = 65-100n
a5 = 65-100*5
a5 = 65-500
a5 = -435
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The first five terms are -35, -135, -235, -335, -435
This can be confirmed using a spreadsheet.
Another verification option is to use the Sequence command in GeoGebra.
The command to type into GeoGebra's input bar would be:
Sequence(65-100*n, n, 1, 5, 1)