mohon bantuannya yah soalnya buat tugas besok !

1) A + B = C

(2x + 5 + 7 ............ 6 + 2) = (4 ...... 8)
(5 + 3y + 1 ....... 20 + (-6)) .. (24 .. 14)

(2x + 12 .... 8) = (4 ..... 8)
(3y + 6 .... 14) .. (24 .. 14)

2x + 12 = 4
2x = -8
x = -4

3y + 6 = 24
3y = 18
y = 6

x + y = (-4) + 6 = 2

2) P = (3 ... 2) maka Pt = (3 ... 5) ==> det Pt = 3.4 - 2.5 = 12 - 10 = 2
........... (5 .. 4) .................... (2 ... 4)

(Pt)^-1 = 1/2 (4 ... -5) = (2 ... -5/2)
.................... (-2 ... 3) .. (-1 ..... 3/2)

3) A . B =
(2 ... -4 .. 3) (1 ..... 5 ... 2)
(1 ..... 2 .. -1) (-1 .. -8 .. -5)
(-2 .. -3 .. 1) (-1 .. -14 .. -8)

(2.1 + (-4)(-1) + 3(-1) ... 2.5 + (-4)(-8) + 3(-14) ... 2.2 + (-4)(-5) + 3(-8))
(1.1 + 2(-1) + (-1)(-1) ..... 1.5 + 2(-8) + (-1)(-14) ....... 1.2 + 2(-5) + (-1)(-8))
(-2.1 + (-3)(-1) + 1(-1) ... -2.5 + (-3)(-8) + 1(-14) .... -2.2 + (-3)(-5) + 1(-8))

(2 + 4 - 3 .... 10 + 32 - 42 .... 4 + 20 - 24)
(1 - 2 + 1 ...... 5 - 16 + 14 ........... 2 - 10 + 8)
(-2 + 3 - 1 .... -10 + 24 - 14 ....... -4 + 15 - 8)

(3 ... 0 .... 0)
(0 ... 3 .... 0)
(0 ... 0 ... 3)

3 (1 ... 0 ... 0)
... (0 ... 1 ... 0)
.... (0 ... 0 ... 1)

3I

Matriks
Matematika Wajib XI

Pembahasan terlampir