(a) 8(4x+3) > -1 + 7x
32x + 24 > -1 + 7x
32x - 7x > -1 -25
25x >-26
x > -26/25
(b) 167 < 6 + 7(2 - 7r)
167 < 6 + 14 - 49r
49r < 6 + 14 - 167
49r < - 147
r < - 3
(c) 8x + 40 > -8 ( 1 - 7x)
8x + 40 > -8 + 56x
56x - 8x < 48
48x < 48
x < 1
(d)5( 6 + 3r) + 7 > 127
30 + 15r + 7 > 127
15r > 127 - 37
15r > 90
r > 6
The y-values are increasing, as x increases in this problem.
Answer:
11 play the flute and piano, while 14 play the flute and 3 play the piano separately, and 10 play neither. That would tell me that it’s just simple addiction, so...
11+14+3+10=38
There are 38 pupils in the class.