Answer:
1) the signs of the numbers is not in standard form
2) always make sure that the signs of the two equations is standarised and then solve
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Answer:

Step-by-step explanation:
The marginal cost function, C'(x), is the derivate of the cost function, C(x).
Therefore, we can obtain the cost function by finding the integral of the marginal cost function:

Where 'a' is a constant and represents fixed costs. If fixed costs are $3,000, the cost function is:

Answer:
is there a question or picture?
The Inequality representing money she can still spend on her friend birthday gift is .
Jordan can still spend at most $30 on her friends birthday gift.
Step-by-step explanation:
Given:
Total money need to spend at most = $45
Money spent on Yoga ball = $15
We need to find how much money she can still spend on her friend birthday gift.
Solution:
Let the money she can still spend on her friend birthday gift be 'x'.
So we can say that;
Money spent on Yoga ball plus money she can still spend on her friend birthday gift should be less than or equal to Total money need to spend.
framing in equation form we get;
The Inequality representing money she can still spend on her friend birthday gift is .
On solving the the above Inequality we get;
we will subtract both side by 15 using subtraction property of Inequality.
Hence Jordan can still spend at most $30 on her friends birthday gift.