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ACT Math 1.3 Elementary Algebra
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ACT Math Elementary Algebra: Drill 1, Problem 3. Solve for y using substitution.

ACT Math 1.4 Elementary Algebra
337 Views

Math Elementary Algebra: Drill 1, Problem 4. Solve for y using substitution.

ACT Math 1.5 Elementary Algebra
264 Views

Math Elementary Algebra: Drill 1, Problem 5. Solve for a using substitution.

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ACT Math 1.5 Elementary Algebra 264 Views


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Description:

Math Elementary Algebra: Drill 1, Problem 5. Solve for a using substitution.

Language:
English Language

Transcript

00:03

Here's your shmoop de jour

00:06

Solve for a using substitution: 4a = b - 8

00:10

a + b = 18

00:13

And here are the potential answers...

00:17

OK fun problem.

00:19

It's another one of those problems that wants us to put our super-duper substitution skills

00:25

to work.

00:28

We want to get either a or b alone. Like what is a simply or what is b simply

00:36

In the first equation, b's already by itself...

00:39

...so we can just add 8 to both sides to get b = 4a + 8.

00:48

Plugging that into the other equation in place of b, we get a + 4a + 8 = 18...

00:54

...and when we slap our a terms together and subtract 8 from each side...

00:58

...we're left with 5a = 10. Divide both sides by 5, and a = 2.

01:04

Our answer is B.

01:05

As in, "Binomial Man."

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