Question

dengan cara yang rinci no ngasal​

Answer 1

Penjelasan dengan langkah-langkah:

1. a. x = 3, y = 9

6x - 8y + 5

= 6(3) - 8(9) + 5

= 18 - 72 + 5

= -49

b. a = -6, b = 8

-7b - a + 9

= -7(8) - (-6) + 9

= -56 + 6 + 9

= -41

2. x = 25, y = -18

3x - 5y

= 3(25) - 5(-18)

= 75 - (-90)

= 75 + 90

= 165

3. xy = 42

x = 42/y

yz = 63

z = 63/y

xz = 54

(42/y)(63/y) = 54

2646/y² = 54

54y² = 2646

y² = 2646 / 54

y² = 49

y = √49

y = 7

x = 42/y

x = 42/7

x = 6

z = 63/y

z = 63/7

z = 9

x² + y² + z²

= 6² + 7² + 9²

= 36 + 49 + 81

= 166