For "HELPCLICK" only_Forums #A

2

40

xx

-=

(4)0

xx

-=

{

}

The solution set is 0,4

0 or 4

xx

=-

0 or 40

xx

=+=

2

60

xx

+-=

2

6

xx

=-

(3)(2)0

xx

+-=

3 or 2

xx

=-=

{

}

The solution set is 3,2

-

2

7

x

=

39

x

+=±

7

x

=±

7 or 7

xx

==-

{

}

The solution set is 7,7

-

(

)

2

39

x

+=

33

x

+=±

33 or 33

xx

+=+=-

0 or 6

xx

==-

{

}

The solution set is 0,6

-

2

2650

xx

+-=

2

265

222

xx

+=

2

265

xx

+=

2

959

3

424

xx

++=+

2

319

24

x

æö

+=

ç÷

èø

319

24

x

+=±

193

22

x

=±-

193193

or

22

x

--

=-

2

2410

xx

-+=

2

0

axbxc

++=

2

40 so there are two real solutions

which can be found using the quadratic f

ormula.

bac

->

22

4(4)4(2)(1)1688

bac

-=--=-=

2

4

2

bbac

x

a

-±-

=

(4)8

2(2)

x

--±

=

48

4

±

=

2

22

±

=

2222

The solution set is ,

22

ìü

+-

ïï

íý

ïï

îþ

2

1

6180

2

xx

-+=

2

12360

xx

-+=

2

40 so there is a repeated solution

which can be found using the quadratic f

ormula.

bac

-=

22

4(12)4(1)(36)1441440

bac

-=--=-=

(12)

0

2(1)

x

--±

=

12

6

2

==

{

}

The solution set is 6

2

232

xx

+=

2

2230

xx

-+=

2

0

axbxc

++=

(

)

2

2

424(2)(3)

42420

bac

-=--

=-=-

2

Since 40,

there is no real solution.

bac

-<

2

12

60

xx

+-=

2

620

xx

+-=

(

)

2

2

414(6)(2)

14849

bac

-=--

=+=

2

Since 40,

there are two real solutions.

bac

->

49

1

2(6)

x

-±

=

17

12

-±

=

171

122

172

123

-+

==

--

==-

12

The solution set is ,

23

ìü

-

íý

îþ

(

)

2

918144

x

-=

(

)

2

1816

x

-=

184

x

-=±

18422 or 14

x

=±=