All Algebra 1 Resources
Example Questions
Example Question #14 : How To Find The Solution To A Quadratic Equation
The product between an integer and another integer that's units greater is equal to . Find these integers.
none of these
We'll call one of the integers , which makes the other integer . The product between and is . This is written as
Solve for .
We can solve this either by using the quadratic formula or by factoring. Factoring seems to be the quickest method.
Take the square root of both sides.
The first integer is , which we can use to find the other integer by using .
The second integer is 2.
Therefore, the two integers are and .
Example Question #66 : Systems Of Equations
Find the solutions:
Since the trinomial starts with , the first term in each of the binomials will be :
Since you have a at the end of the trinomial, the two terms at the end of the two binomials must multiply to . Since it is a negative , the signs in the two binomials will be opposite.
and work:
Now you set each binomial equal to independently, and solve for .
Example Question #16 : Quadratic Equations
Solve the following quadratic equation:
FOIL (first, outside, inside, last) is a device to help students remember to multiply every term by every other term exactly one time. The steps of using FOIL progress as follows:
1) Multiply the first term of each parenthetical expression together:
2) Next, multiply the "outside" terms together:
Add that to the first product, since the terms are all being added together in the parentheses, and the distributive property requires that we maintain the sign:
3) Multiply the "inside" terms together:
Add that to the first two products:
4) Finally, multiply the last terms from each parenthetical expression together:
Add all of the terms together and combine like terms where possible:
5) We now have a quadratic equation. In order to solve a quadratic, we must first set our expression equal to zero by subtracting 6 from both sides.
6) Next, we factor by using backwards distribution. The idea is to split up the middle term, , in such a way that one part has a common factor with and the other part has a common factor with 6. We can then factor by grouping. Obviously, no matter how we split up , one part will always contain an . So we must focus our attention on the 6. What are the factors of 6 that add up to 7?
Yes!
So,
7) Now we pull out the common factor from each pair of terms, from the first and 6 from the second:
8) Now we factor again, taking out the common factor from each term:
9) We know that at least one of the terms must be equal to zero in order for the product to equal zero, so we set each part equal to zero and solve:
and
Example Question #93 : Single Variable Algebra
Where do the graphs of these two equations intersect?
Equation 1:
Equation 2:
One can find the points of intersection of these two functions by setting them equal to one another, essentially substituting in one equation for the -side of the other equation. This will tell us when the (output) will be the same in each equation for a given (input).
By simplifying this equation and setting it equal to zero, we can find the two -values that produce the same values in the system of the two equations.
Subtract from both sides of the equation, and add to both sides.
Factoring this last equation makes it easier to find the -values that will result in zero on the left side of the equation. Set the two parenthetical phrases equal to zero to find two separate -values that satisfy the equation. These values will be the values of the points of intersection between the two equations.
We know our factors multiply to , and the six times one factor plus the other is equal to
and , so and are our factors.
Substituting these two values into either of the two original equations results in the -values of the points of intersection.
are the points of intersection.
Example Question #2 : Finding Zeros Of A Polynomial
Solve for x.
x = 4, 3
x = –5, –2
x = 5
x = –4, –3
x = 5, 2
x = 5, 2
1) Split up the middle term so that factoring by grouping is possible.
Factors of 10 include:
1 * 10= 10 1 + 10 = 11
2 * 5 =10 2 + 5 = 7
–2 * –5 = 10 –2 + –5 = –7 Good!
2) Now factor by grouping, pulling "x" out of the first pair and "-5" out of the second.
3) Now pull out the common factor, the "(x-2)," from both terms.
4) Set both terms equal to zero to find the possible roots and solve using inverse operations.
x – 5 = 0, x = 5
x – 2 = 0, x = 2
Example Question #2 : Finding Roots
Solve for x.
x = 5, 2
x = –4, 4
x = –5, –2
x = 2
x = –4
x = –4
1) First step of solving any equation: combine like terms. With quadratics, the easiest step to take is to set the expression equal to zero.
2) There are two ways to do this problem. The first and most intuitive method is standard factoring.
16 + 1 = 17
8 + 2 = 10
4 + 4 = 8
3) Then follow the usual steps, pulling out the common factor from both pairs, "x" from the first and "4" from the second.
4) Pull out the "(x+4)" to wind up with:
5) Set each term equal to zero.
x + 4 = 0, x = –4
But there's a shortcut! Assuming the terms are arranged by descending degree (i.e., ), and the third term is both a perfect square whose square root is equal to half of the middle term, mathematicians use a little trick. In this case, the square root of 16 is 4. 4 * 2=8, so the trick will work. Take the square root of the first and last term, then stick a plus sign in between them and square the parentheses.
And x, once again, is equal to –4.
Example Question #3 : Solving Quadratic Equations
Solve for :
To factor, find two numbers that sum to 5 and multiply to 6.
Check the possible factors of 6:
1 * 6 = 6
1 + 6 = 7, so these don't work.
2 * 3 = 6
2 + 3 = 5, so these work!
Next, pull out the common factors of the first two terms and then the second two terms:
Set both expressions equal to 0 and solve:
and
Example Question #191 : Equations / Inequalities
Solve for .
Notice that both terms have in them. Factor this out:
Set both factors equal to zero and solve for .
Example Question #22 : How To Find The Solution To A Quadratic Equation
Solve for :
Hint: Quadratic Formula
First, we want to use the quadratic formula for this equation, to find the values for x:
When the quadratic formula is simplified, it should look like this:
This provides us with 2 possible values for x:
and/or
To confirm whether or not these are values of X, we need to plug them in, to see if the equation makes sense:
12+24-36 = 0, x = 2
108-72-36 = 0, x = -6
Therefore,
x = 2 and x = -6
Example Question #73 : Systems Of Equations
Solve for :
We know that this equation can be simplified to the following format:
(X+_)(X+_) = 0
X will be cross-multiplied by X to form the of the equation. We need to plug in number values that will result in 4x and 3 when cross-multiplied:
(X+3) = 0, X = -3
(X+1) = 0, X = -1