0:02 if you find a problem on the GED math
0:04 test but the answers look a little
0:07 strange like these guys with a plus
0:10 minus symbol and a square root and a
0:12 fraction then the way they found it is
0:15 with the quadratic formula and this is
0:17 on the formula sheet that they'll give
0:20 you so you don't have to memorize it but
0:22 the key to solving it is you just need
0:26 to plug in a b and c in for the values
0:30 here but to find them a is always in
0:33 front of x s so in this case a is just
0:36 two and then B that's the number in
0:39 front of X so B is 7even but then we
0:42 want all these numbers on the same side
0:44 we're going to have to move anything on
0:46 the right side of the equal sign over to
0:49 the left side and when you move a number
0:51 from one side of the equal sign over to
0:54 the other it's going to flip the sign so
0:57 it's going to become a positive four so
1:00 there's a b and c right there but really
1:02 quickly the reason that worked you want
1:05 the right side to become zero so we're
1:08 going to do the opposite of minus 4 + 4
1:11 that gets those to cancel but whatever
1:13 you do to one side of the equal sign you
1:16 have to do to the other so that's why C
1:18 in this case becomes
1:20 four next we're going to break out the
1:22 calculator we're going to store these
1:26 values as a b and c so let's see how we
1:30 do that okay so if we want a to be two
1:32 just start with the number and this is
1:35 the store button then click the variable
1:38 button right above it till you get to a
1:42 and then hit enter so a is two right
1:45 there keep going B is seven start with
1:47 the number first we're going to store
1:51 that as B and there we have it enter and
1:55 C's four so four first store and keep
1:59 going till we get to C and boom okay
2:00 from here here we're actually going to
2:03 type in the whole quadratic formula so
2:05 let's clear and let's do that we'll
2:08 start with a fraction then we have a
2:10 negative B so let's hit the white button
2:13 for the negative keep going till we get
2:16 to B then we have either a plus or a
2:19 minus you could always just do a plus
2:22 sign here then a square root will go
2:25 second X2 to get the square root and we
2:28 have b^ squared so you know what to do
2:30 just keep going and then we want it
2:32 squared use the button right above it
2:36 there okay then it's going to be - 4 * a
2:40 * C so we'll do minus 4 but I like to
2:43 multiply these so times go ahead and
2:46 find a and go ahead and multiply that times
2:49 times
2:52 C okay the top is all good finally the
2:55 Bottom's just going to be 2 * a so sneak
2:57 down there two and you can just mush
3:01 them next to each other and there's 2 AA
3:03 so once you've typed in the quadratic
3:06 formula just go ahead and hit enter and
3:08 this is going to be our answer so let's
3:10 go ahead and clear these out and let's
3:12 see which matches here we've got a
3:16 square OT of 17 this one has it and this
3:20 one has it we've got a minus 7 or a -7
3:22 they both have that but then the
3:24 denominator the bottom is four so
3:28 automatically it's got to be B here and
3:31 of course I only made it a 50/50 but
3:32 you'd easily find it if there were four
3:36 of those as well so that's it just set
3:39 it up find your A and C store those
3:42 numbers and then plug into the quadratic
3:45 there okay let's check out one more
3:48 example here so once again you notice
3:50 these weird answers you're thinking okay
3:52 it's got to be the quadratic formula
3:55 let's go ahead and find our a b and c
3:59 well we know a is 5 B's -2 but let's go
4:02 aead ahead and move eight over it's a
4:04 positive 8 we move it to the left side
4:08 it'll become a negative 8 so there's our
4:12 A5 B is -2 if there's a minus sign it's
4:16 negative and C similarly that's
4:18 ne8 all righty let's go ahead and store
4:21 these here we'll start with five we're
4:23 going to store that as
4:28 a enter and then we've got -2 that's B
4:30 we'll start with -2
4:32 again don't forget to
4:41 ne8 and by the way if you accidentally
4:44 skip over it they just keep cycling
4:46 through so just keep hitting that till c
4:47 pops up
4:50 again and now let's go ahead and clear
4:51 these we've stored those we'll go ahead
4:54 and type in the quadratic formula we got
4:57 our fraction negative
5:02 B we'll use our plus Square < TK and
5:04 then b^
5:09 2 and minus 4 *
5:12 a Time
5:15 C it is a bit of a pain but just take
5:19 your time you got it all divided by
5:24 2A and there we go so drum roll enter
5:26 and this is the final answer here so
5:28 we'll get these out of the way and let's
5:31 see we've got a square OT of 41 they
5:34 both have that but it does have a plus
5:37 one so only the top is correct because
5:39 this would be a negative one or a minus
5:43 one and they're both divided by five so
5:45 in other words a that's got the right
5:48 stuff and that's it here now if you're
5:50 just looking to pass the GED tests I
5:52 wouldn't worry about these but if you're
5:54 looking to score a little bit higher or
5:56 get a college ready this can be a really
5:58 helpful way to get these questions
6:00 correct here
6:02 big shout out to Mr Weiss and Weiss
6:05 videos he shows this technique in a
6:08 video he published a few years back so I
6:10 just wanted to show a nice easy way to
6:13 solve using the quadratic formula check
6:15 out my website for practice problems
6:18 just like these guys and here's a video
6:20 If you're looking for other types of
6:22 quadratic equations that you could solve
6:25 with the calculator all righty let me
6:26 know what questions you have what else
6:28 you want me to cover we we'll see you in
6:30 the next video toodles
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