All Algebra II Resources
Example Questions
Example Question #3 : How To Find The Solution To A Rational Equation With Lcd
Solve the rational equation:
no solution; is extraneous
With rational equations we must first note the domain, which is all real numbers except . (If , then the term will be undefined.) Next, the least common denominator is , so we multiply every term by the LCD in order to cancel out the denominators. The resulting equation is . Subtract on both sides of the equation to collect all variables on one side: . Lastly, divide by the constant to isolate the variable, and the answer is . Be sure to double check that the solution is in the domain of our equation, which it is.
Example Question #111 : Solving Rational Expressions
Solve for :
There is no solution.
Subtract 1 from both sides, then multiply all sides by :
A quadratic equation is yielded. We can factor the expression, then set each individual factor to 0.
Both of these solutions can be confirmed by substitution.
Example Question #1812 : Algebra Ii
Solve for :
In order to solve for , we need to consider this equation as two proportions being set equal:
Now, we can cross-multiply.
Distribute the on the right side:
Subtract from both sides to start combining like terms:
Now, this is just a two-step equation. Start by subtracting from both sides:
Divide by .
Example Question #1813 : Algebra Ii
Solve for :
and
Imaginary solution
First, cross-multiply:
Once we simplify we are left with the following two quadratic equations:
In order to solve a quadratic, we need to have it equal to zero and then we can use the quadratic formula. What we need to do now is combine like terms. We can subtract all of the terms on the left from the like terms on the right:
This gives us:
Now we can use the quadratic formula:
Where the quadratic equation follows the pattern:
Therefore, we can use the terms in our quadratic equation and rewrite the equation as follows:
Since we can re-write as and , our answer becomes
Example Question #13 : Solving Rational Expressions
Solve for :
Imaginary solution
Consider this problem as 2 proportions set equal:
Now, we can cross-multiply.
Using FOIL (method of simplifying binomials by multiplying following the pattern of first terms, outer terms, inner terms, and last terms), we can multiply the binomials on the right giving us:
In order to solve this equation, we need to have one side of the equation equal to .
Add to both sides.
Now, we can solve by using the quadratic formula, or by factoring. If we factor, we get:
Solving for each equation leaves us with the following answers:
and
Example Question #1814 : Algebra Ii
Solve for :
Imaginary solution
In order to solve, we need to first cross-multiply.
Using FOIL (method of simplifying binomials by multiplying following the pattern of first terms, outer terms, inner terms, and last terms), we can multiply the binomials on the left giving us:
In order to continue solving this quadratic, we need to subtract from both sides so that the quadratic is equal to .
Now, we can solve using the quadratic formula:
Where the quadratic equation follows the pattern:
Therefore, we can use the terms in our quadratic equation and rewrite the equation as follows:
Since we can re-write as and , our answer becomes:
Example Question #1811 : Algebra Ii
Solving Rational Expressions
Solve the below equation for :
When solving two rational expressions that are set equal to each other Cross Multiply.
In this case we will multiply 4 by the the (3x-2), and also multiply 5 by the (2x+7)
Distribute on both sides to get:
Subtract 10x from both sides to get:
Add 8 to both sides to get:
Divide both sides by 2 to get the final solution:
Finally, double check for extraneaous solutions. Anytime you might get a zero in the bottom of a fraction, this is considered extraneaous because it is a mathematical impossibility to divide by zero.
In this case there are no x values in the denominators of the original problem, so there are no extraneaous solutions and the only solution will be:
Example Question #112 : Solving Rational Expressions
If , what is ?
We start by taking the original function, and replacing all the 's with . We end up with:
Then we can solve like normal:
If we noticed it, we also could have factored the numerator into:
The terms would have canceled leaving:
Solving that would have been much easier:
Either way, we would still get the exact same answer.
Example Question #17 : Solving Rational Expressions
If , find .
When we first look at this problem, we might be panicking because just plugging into the function makes us divide by , which we don't like. For now, let's forget about the denominator and focus on the numerator. If we look closely, we can see that we can factor the numerator:
Giving us:
As we can see, the will cancel from the numerator and the denominator, clearing up our "divide by 0" problem:
Now we can solve:
Example Question #152 : Rational Expressions
If and , what is ?
To begin, let's write the whole problem out plainly:
From here, in order to add the two fractions, we need to get the denominators to be the same. To do this, we multiply the numerator and denominator of each fraction by the denominator in the OTHER fraction:
Now we can add the fractions together:
Now we can expand using FOIL:
Finally, we collect like terms in the numerator for a final answer of: