a. 95/225 b. 97/225 c. 99/225 d. 101/225 e. 103/225 plis bantuin dr tadi ga nemu2 jawabannya kalo ak.... Question from @bestienemy

YL2793

9(a - 2b) + (a + 2b) = 2(a + 2b)(a - 2b)

9(a - 2b) + 2 (a + 2b) = -1(a + 2b)(a - 2b) -

--------------------------------------------------------

- (a + 2b) = 3 (a + 2b)(a - 2b)

(a - 2b) = - 1/3

$\\ \\$

9 (- 1/3) + (a + 2b) = 2(a + 2b)(- 1/3)

-3 + (a + 2b) = -2/3 (a + 2b)

-3 = -2/3 (a + 2b) - (a + 2b)

-3 = -5/3 (a + 2b)

(a + 2b) = 9/5

$\\ \\$

a - 2b = -1/3

a + 2b = 9/5 +

-----------------

2a = -1/3 + 9/5

2a = -5/15 + 27/15

2a = 22/15

a = 11/15

$\\ \\$

a + 2b = 9/5

11/15 + 2b = 9/5

2b = 9/5 - 11/15

2b = 27/15 - 11/15

2b = 16/15

b = 8/15

$\\ \\$

$a - {b}^{2} = \\ \\ \frac{11}{15} - { (\frac{8}{15}) }^{2} = \\ \\ \frac{11}{15} - \frac{64}{225} = \\ \\ \frac{165}{225} - \frac{64}{225} = \frac{101}{225}$

$\\ \\$

Jawabannya D

0 votes Thanks 1

bestienemy makasi banyak yaaa ㅠㅠ

hendrisyafa

Jawab:

misal :

$A=\frac{9}{a+2b}$

$B=\frac{1}{a-2b}$

Bentuk persamaan diubah :

A + B = 2

A + 2B = -1

_________ -

-B = 3

B = -3 ---> $-3=\frac{1}{a-2b}$

-3a + 6b = 1

A + (-3) = 2

A = 5 ---> $\frac{9}{a+2b}=5$

5a+10b = 9

-3a + 6b = 1 .... x 5 = -15a + 30b = 5

5a + 10b = 9 ......x 3 = 15a +30b = 27

___________ +

60b = 32

b = $\frac{32}{60} = \frac{8}{15}$

-3a + 6b = 1

-3a = 1- 6b

= $1-6(\frac{8}{15} )$

= $\frac{15}{15} -\frac{48}{15}$

= $-\frac{33}{15} =-\frac{11}{5}$

a = $\frac{11}{15}$

maka : a - b² = $\frac{11}{15}-(\frac{8}{15} )^{2}$

= $\frac{11}{15}-\frac{64}{225}$

= $\frac{165}{15}-\frac{64}{225}$

= $\frac{101}{225}$

1 votes Thanks 1

bestienemy makasi banyak yaa ^^

cieknock80 Oi Bang Makasih Udah Jawab Pertanyaan Aku Tadi :)

bestienemy yoi sama2

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