NÅGRA KOMMENTARARER TILL LÖSNINGARNA

2654c
−3
4,5 ⋅ 10 ( x + 200) = 9
−3 −3
4,5 ⋅10 ⋅ x + 4,5 ⋅10 ⋅ 200 = 9
0,0045x + 0,9 = 9
0,0045x = 9 −0,9
0,0045x = 8,1
8,1
x = = 1800
0,0045
2655a
y = kx+ a
kx + a = y
kx = y −a
y−a k =
x
2659a
p= 4t−5 4t− 5=
p
4t = p+
5
p + 5
t =
4
( byt led )
( byt led )
2661a
A = P + PRT
P + PRT = A
PRT = A −P
A−P R =
PT
( byt led )
2670a
7x+ 3= 5x+ 17
7x+ 3−5x− 17= 0
2x− 14= 0 ( div 2)
x − 7= 0 ( flytta om)
x = 7
( flytta om)
LÖSNINGAR DEL B
2655b
y−a k =
x
17 − 5
k = =−3
−4
2659c
v= u+ at
u+ at = v
at = v −u
v−u t =
a
( byt led )
2661d
L= a+ nd −d
a+ nd − d = L
nd = L − a + d
L− a+ d
n =
d
( byt led )
2654d
−4
2⋅ 10 ( R + 750) = 0,35
0,0002( R + 750) = 0,35
0,0002R + 0,15 = 0,35
0,0002R = 0,35 −0,15
0,0002R = 0,20
0,20
R = = 1000
0,0002
2658a
P= Q−3
Q− 3 = P
Q= P+
3
2660a
y = ax+ b
ax + b = y
ax = y −b
y−b x =
a
2670c
5( t + 3) − 11 = 24
5( t + 3) −11− 24 = 0
(5t + 15) −11− 24 = 0
5t+ 15−11− 24= 0
5t− 20= 0 ( div 5)
t − 4= 0 ( flytta om)
t = 4
( byt led )
( byt led )
2662a
3x+ 4y− 13= 0
3x= 13−4y 13− 4y
x =
3
( flytta)
2658d
q− px= r
− px = r −q
px =− r + q
byt plats
q−r p =
x
2660d
S = 2πrh+ 2πr
2π 2π
2πrh = S −2πr
2
S−2πr h =
2π
r
47
( byt tecken)
2
( byt led )
2
rh + r = S
2
2662d
8x−12y− 17= 0
− 12y=− 8x+ 17
12y= 8x−17 8x−17 y =
12
2670d
3( x+ 4) = 19 + 5( x−1)
3( x+ 4) −19−5( x−
1) = 0
(3x+ 12) −19 −(5x− 5) = 0
3x+ 12−19− 5x+ 5= 0
−2x− 2= 0 ( div − 2)
x + 1= 0 ( flytta om)
x =−1
( byt tkn)
( flytta om)