mohon bantuannya tolong bantu jawab?

[1]
a] 35 - 23x2 + 15:3 = 35 - 46 + 5 = -6
b] 3/5 + 5/8 - 5/10 + 2 = (24+25-20+80)/40 = 109/40 = 2 29/40
c] v18 + v64 + v50 = v9.2 + 8 + v25.2 = 3v2 + 8 + 5v2 = 8(v2 + v1)
Ket : v dibaca akar


[2]
 2x - y = 3
-3x - y = 8
------------- (-)
5x      = -5
  x      = -1

2x - y = 3
2(-1) - y = 3
-2 - y = 3
-y = 5
y = -5


[4]
y - y1 = m(x - x1)
y - (-3) = 2(x - 1)
y + 3 = 2x - 2
y - 2x - 5 = 0


[5]
(y - y1)/(y2 - y1) = (x - x1)/(x2 - x1)
(y - (-2))/(-5 - (-2)) = (x - 1)/(2 - 1)
(y + 2)/-3 = (x - 1)
y + 2 = (x - 1)3
y + 2 = 3x - 3
y - 3x + 5 = 0


[6]
Un = 3 - 2n
U1 = 3 - 2(1) = 1
U2 = 3 - 2(2) = -1
U3 = 3 - 2(3) = -3
U4 = 3 - 2(4) = -5
U5 = 3 - 2(5) = -7

Jadi, suku ke 1 hingga ke 5 secara berurutan adalah 1, -1, -3, -5, dan -7


[8]
Diketahui :
Barisan geometri : 2, 6, 18, 54

Ditanya :
a = ?
r = ?
U9 = ?

Penyelesaian :
a = U1 = 2

U2 = 6
ar = 6
2r = 6
r = 6/2 = 3

U9 = a.r^8 = 2(3^8) = 2(6561) = 13122


[9]
Diketahui :
U1 = a = 3
U5 = -5

Ditanya :
S10 = ?

Penyelesaian :
U5 = -5
a + 4b = -5
3 + 4b = -5
4b = -5 -3
b = -8/4 = -2

Sn = (n/2)(2a + (n-1)b)
S10 = (10/2)(2(3) + (10-1)-2) = 5(6 - 18) = 5(-12) = -60


[10]
Diketahui :
Barisan aritmetika : 2, 6, 10, 14

Ditanya :
U25 = ?

Penyelesaian :
a = U1 = 2
b = U2 - U1 = 6 -2 = 4
Un = a + (n-1)b
U25 = 2 + 24(4) = 2 + 96 = 98