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Example Questions
Example Question #33 : Algebraic Fractions
Simplify:
Begin by simplifying the numerator.
has a common denominator of . Therefore, we can rewrite it as:
Now, in our original problem this is really is:
When you divide by a fraction, you really multiply by the reciprocal:
Example Question #34 : Algebraic Fractions
Simplify:
Begin by simplifying the numerator and the denominator.
Numerator
has a common denominator of . Therefore, we have:
Denominator
has a common denominator of . Therefore, we have:
Now, reconstructing our fraction, we have:
To make this division work, you multiply the numerator by the reciprocal of the denominator:
Example Question #31 : Algebraic Fractions
Simplify:
None of the other answer choices are correct.
Recall that dividing is equivalent multiplying by the reciprocal. Therefore, ((x - 4) / (1 / 2)) / (1 / (x + 4)) = ((x - 4) * 2) * (x + 4) / 1.
Let's simplify this further:
(2x – 8) * (x + 4) = 2x2 – 8x + 8x – 32 = 2x2 – 32
Example Question #32 : Algebraic Fractions
Solve for :
Begin by isolating the variables:
Now, the common denominator of the variable terms is . The common denominator of the constant values is . Thus, you can rewrite your equation:
Simplify:
Cross-multiply:
Simplify:
Finally, solve for :
Example Question #23 : Algebraic Fractions
Evaluate when x=11. Round to the nearest tenth.
1.8
1.9
0.2
0.3
1.8
Wherever there is an x, plug in 11 and perform the given operations. The numerator will be equal to 83 and the denominator will be equal to 46. 83 divided by 46 is equal to 1.804… and since the second decimal place is not greater than or equal to 5, the first decimal place stays the same when rounding so the final answer is 1.8.
Example Question #45 : Algebraic Fractions
Find the inverse equation of:
To solve for an inverse, we switch x and y and solve for y. Doing so yields:
Example Question #2 : How To Find Inverse Variation
Find the inverse equation of .
1. Switch the and variables in the above equation.
2. Solve for :
Example Question #3 : How To Find Inverse Variation
When , .
When , .
If varies inversely with , what is the value of when ?
If varies inversely with , .
1. Using any of the two combinations given, solve for :
Using :
2. Use your new equation and solve when :
Example Question #33 : Algebraic Fractions
x |
y |
If varies inversely with , what is the value of ?
An inverse variation is a function in the form: or , where is not equal to 0.
Substitute each in .
Therefore, the constant of variation, , must equal 24. If varies inversely as , must equal 24. Solve for .
Example Question #1 : How To Find Inverse Variation
Two numbers and vary inversely, and when . If this is true, what is the value of when ?
If when , and the variation is direct, then . Using this, we know that if , .
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