1 час = 60 мин. 120 сек = 2 мин. (812): 29-7)*14= 98
1) y=2(x+7)
2) y=7(5-a)
3) y= (c-6)×12
4)y=14(3a-2)
5)8(4a-3b+11c)= 32a-24b+88c
6)(16x+11y-23)= 240x+165y-345
0,6( 2х²+ 3 ) - 7( 2 - х²) = 2( 3х²+ 1 ) - 1
3/5 × ( 2х²+ 3 ) - 14 + 7х² = 6х²+ 2 - 1
6/5х²+ 9/5 - 14 + 7х² = 6х²+ 2 - 1
41/5х²- 6х² = 1 + 61/5
11/5х² = 66/5
х² = 6
х = + √6
х = √6
х = - √6
х = √6., х = - √6