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ACT Math: Pre-Algebra Drill 5, Problem 2. If a and b are prime numbers, how many factors does ab have?
ACT Math 2.1 Pre-Algebra 380 Views
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Description:
ACT Math: Pre-Algebra Drill 2, Problem 1. Solve for x in this equation.
Transcript
- 00:03
Here's your Shmoop du jour...
- 00:05
Solve for X.
- 00:06
3x plus seven X plus nine equals 35 and here are the potential answers:
- 00:14
Okay, so what is this problem asking us to do?
- 00:16
Well, it's really just a straightforward "Solve for X" dance.
Full Transcript
- 00:19
We just combine terms to simplify and we're there...
- 00:23
...wherever there is....but okay we have 3x, 7x which we can add
- 00:27
to get 10x. We can subtract 9 from both sides
- 00:31
35 -9 is 26, so we have 10x equals 26.
- 00:36
Now divide both sides by 10
- 00:38
and X equals 26 over 10. Done.
- 00:42
Wait...not done...there's no 26 over 10 in the answers.
- 00:46
What did we do wrong? Well, we need to reduce.
- 00:49
10 and 26 are even numbers
- 00:51
so if nothing else we can divide 2 into each of them evenly
- 00:54
and getting now reduced 13 over 5 which ta-da
- 00:58
is here. Answer C.
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