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SAT Math 1.3 Numbers and Operations. x and y must be which of the following?
SAT Math 1.4 Algebra and Functions 207 Views
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Description:
SAT Math 1.4 Algebra and Functions. Solve for x.
Transcript
- 00:02
Here’s your shmoop du jour, brought to you by complex equations.
- 00:07
If you think solving one is tough, try dating one.
- 00:11
For the equation: 2 to the power of 2x plus 4 equals 4 to the power of x plus 2...
- 00:16
Solve for x. And here are your potential answer...
- 00:21
Interesting...the x's are all in the exponents of this equation...
Full Transcript
- 00:24
…which means we'll be using our basic exponent rules to solve for x.
- 00:28
Good thing we’ve got those babies in our bag of tricks.
- 00:31
Ok, so the first thing that's important to notice is that 4 is the same as 2 squared,
- 00:35
so we can rewrite the second half of our equation as: 2 to the power of 2 times x plus 2.
- 00:43
2 times x plus 2 equals 2x plus 4... so our equation becomes:
- 00:47
2 to the 2x plus 4 equals 2 to the 2x plus 4.
- 00:52
Golly… they’re twins! Aw!
- 00:55
Ok… what this actually means is that we can substitute
- 00:58
any real number for x and the equation would be true....
- 01:07
So D… All real numbers…is our answer.
- 01:11
Look how adorable they look in matching fisherman hats!
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