In multiplication, a negative times a positive has a negative answer. if both are positive or both are negative, the answer is positive.
5 * -5 = -25
-5* -5 = 25
in divisions say you have
-5/5 = -1
-5/-5= 1
5/-5= -1
in addition and subtraction, subtracting a negative means to add the two numbers. adding a negative means to subtract the second number.
5+ (-5) = 0
5- (-5) = 10
I set this up as an inequality,

. If you take the cubed root of 800, you get the lower bound of the side length, which is 9.2. Then I just worked my way up until I hit the first number that put me over a volume of 800. That number is 9.29, because 9.28 cubed is 799.1 (not high enough) and 9.29 cubed is 801.8. Therefore, the bounds of the sides exist within a conjunction:

. That's the best I could come up with to help on that one. Wasn't sure if there was another method you were taught at school. I just used common sense more than any rule.
Answer:
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Step-by-step explanation:
Given
In 1990; Income= $39000
In 2010; Income= $70768
Solving (a): An equation in form of f(x) = ax + b
First, we need to determine the slope, a

Taking y as income and x as year index.
When x = 0; y = 39000
When x = 20; y = 70768
Substitute these values in the above formula



Next, is to determine the formula using:

<em>Considering :When x = 0; y = 39000, we have</em>
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<em>Make y the subject of formula</em>
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<em>Express y as a function of x</em>
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Solving (b): Income in 2005
<em>In 2005, x = 15</em>
So:
becomes


Answer:
CBD = 63 degrees
Step-by-step explanation:
To find CBD, we must first find the value of x. To do so, we use this equation since CBD and ABC equal 96 degrees:
(6x+27) + (7x-9) = 96
13x+18 = 96
13x+18-18 = 96-18
13x = 78
13x/13 = 78/13
x = 6
Now that we know the value of x, we factor it in to CBD to find its true value:
6x+27
6(6)+27
36+27
= 63 degrees
To check if this answer is correct, we can also find the value of ABC and see if the two values equal 96:
7x-9
7(6)-9
42-9
= 33 degrees
63 + 33 = 96
The answer is correct. CBD = 63 degrees and ABC = 33 degrees.