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ACT Math: Coordinate Geometry Drill 1, Problem 1. Which inequality is expressed by the number line?
ACT Math: Intermediate Algebra: Drill 3, Problem 1. Find the fifth number in the series.
ACT Math Intermediate Algebra Drill 2, Problem 2. How else can the expression be written?
ACT Math 3.3 Intermediate Algebra 270 Views
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Description:
ACT Math: Intermediate Algebra Drill 3, Problem 3. Solve the equation for x.
Transcript
- 00:03
Hope you're wearing your smartypants and/or thinking cap for this one.
- 00:07
Solve the following equation for x: y equals three halves x plus 4
- 00:12
4 y equals x plus 1
- 00:14
And here are the potential answers...
- 00:21
OK so what is this question asking?
Full Transcript
- 00:22
It's really just a "substitute n' solve" problem.
- 00:26
In the first equation, y is already isolated, so let's just substitute the first equation
- 00:32
into the second.
- 00:37
4 times the quantity 3 halves x plus 4 equals x plus 1.
- 00:44
Multiplying the 4, we get that 12x over 2... or just 6x... plus 16 equals x plus 1.
- 00:57
We combine like terms...so anything with an x goes together and both constants go together.
- 01:02
5x equals negative 15. Divide 5 from both sides, and we get x equals negative 3.
- 01:08
Looks like our answer is B.
- 01:09
As in, "Bad managing decision."
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