C^2+7 would equal 88. the first equation states that C=9, so you can just plug in 9 for C
To solve:
find the square root of both sides
2x-3=±10
Answers:
x=-7/2
x=13/2
If you would like to know which expression represents the amount of time Joe exercises, you can calculate this using the following steps:
Keith ... x hours a week
Troy ... three hours less than Keith: x - 3
Joe ... two times more than Troy: 2 * (x - 3)
The correct result would be D) 2 * (x - 3).
It is not a function—an element from the domain is paired with more than one element from the range. Specifically, the input value of 4 corresponds to two output values: 5 and -4.
A function can only take on one output for each input. It only takes one input value to associate with more than one output value to be invalid as a function.
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