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This video covers both independent and dependent events, although we much prefer independent events. Dependent events are just so dang clingy.
Disjoint events are events that cannot happen at the same time. If one happens, the other doesn't. Simple as that. Overlapping events, on the other...
SAT Math 1.1 Numbers and Operations. How many combinations of beverage and cereal can be made?
ACT Math 1.3 Intermediate Algebra 639 Views
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Description:
ACT Math Intermediate Algebra Drill 1, Problem 3. Can you find the value of a in this expression?
- Intermediate Algebra / Quadratic equations (Quadratic Formula)
- Product Type / ACT Math
- Foreign Language / Arabic Subtitled
- Foreign Language / Spanish Subtitled
- Foreign Language / Korean Subtitled
- Foreign Language / Chinese Subtitled
- Algebra / Understand the relationship between zeros and factors of polynomials
- Algebra / Understand the relationship between zeros and factors of polynomials
- Algebra / Solve equations and inequalities in one variable
- Algebra / Solve equations and inequalities in one variable
- Algebra / Solve equations and inequalities in one variable
- Algebra / Solve equations and inequalities in one variable
- Algebra / Understand the relationship between zeros and factors of polynomials
- Intermediate Algebra / Quadratic formula
Transcript
- 00:02
And here's another shmoop de jour...
- 00:04
Solve for a: 2a squared plus 4a minus 1 equals 0.
- 00:08
And here are the potential answers...
- 00:14
Before we even think about starting, we should always glance at the potential answer set first
- 00:19
Here, the numbers scream at us that the quadratic equation will be involved.
Full Transcript
- 00:23
The quadratic equation looks like this:
- 00:26
We are drawing from a line of the equation "ax squared plus bx plus c."
- 00:31
...and we have to figure out what a, b and c are so we can plug them into the right places.
- 00:37
In this case, the 2 comes from here; it's A.
- 00:39
B is here, and it's 4.
- 00:42
And C is here, and it's negative 1.
- 00:45
Now we just plug in the numbers and this is what we get.
- 00:47
Now we just have to simplify. We get negative 4 plus or minus 4 squared which is 16....
- 00:53
...minus 4 times 2, then times negative 1...
- 00:57
... so it's plus 8... and we get negative 4 plus or minus 16 plus 8, or 24, here under
- 01:02
the square root symbol...
- 01:03
...all over 2 times 2, or 4.
- 01:07
Simplify one more time and we have...
- 01:09
Both A -- here... and B -- here.
- 01:12
Answer: D.
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