1.
a) 60p
b) 12z+5
c) 100a + 4
d) 100x+2*10
2.
a) x = -5
3x - 4 = 3*(-5) - 4 = -15 - 4 = -19
b) y = 2
-9 - 2y = -9 - 2*2 = -9 - 4 = -13
c) x = 3 i y = -4
3x + 2y = 3*3 + 2*(-2) = 9 + (-4) = 9 - 4 = 5
d) a = 9
1/3a(a - 4) = 1/3a^2 - 4/3a = 1/3*81 - 12 = 27 - 12 = 15
3.
a) 3x - 5 + 6x - 2x + 3 +4x = 13x - 2
b) 6,5a + 0,1a + a - 0,1 = 7,6a - 0,1
c) 1/3y + 3y +4 + 2/3y -5 = 4y - 1
4.
a) 30 - x = 9
b) n + 4 = 11
c) 2y = 50
5.
a)
x = ilość małych słoików
0,4*9 + 0,3x = 8,7
b)
x = liczba biletów normalnych
15*302 + 19x = 9033
6.
TAK
TAK
TAK
TAK
7.
a)
12 + 3x = 24 |-12
3x = 12 |/3
x = 4
b)
6y - 4,5 = -23,7 |+4,5
6y = -17,2 |/6
y = 43/15
c)
7x - 6 - 5x = 10 |+6
2x = 16 |/2
x = 8
8.
a)
180° = 80° + α + 4α |-80°
100° = 5α |/5
α = 20°
b)
12 = a + 3a - 8 |+8
20 = 4a |/4
a = 5
9.
a)
3*1,2 + x = 5
3,6 + x = 5 |-3,6
x = 1,4
b)
x + 2x = 33
3x = 33 |/3
x = 11
10.
25 = x + x + 1/2x
25 = 2,5x |/2,5
x = 10 (ramię)
10/2 = 5 (podstawa)
11.
630 = 12(1/6*1/2x)
630 = 12*1/3x
630 = 4x |/4
x = 157,5
157,5 = 7/6y |/(7/6)
y = 135
*12.
p = pomarańcze
c = cytryny
b = banany
30 = c + p + b
c = b + 5
p = c + b
p + b + 5 + b = 30
p + 2b + 5 = 30
2(2b + 5) = 30
4b + 10 = 30 |-10
4b = 20 |/4
b = 5
c = b + 5
c = 5 + 5
c = 10
p = 30 - b - c
p = 30 - 5 - 10
p = 15
