24) 2(ax-b)=cx+3d 2ax - 2b = cx + 3d 2ax - cx = 2b + 3d (2a - c)x = 2b + 3d x = (2b + 3d)/(2a - c)
31) Find a number which decreased by 18 is 5 times its opposite. x: the number x - 18 = 5 (-x) 6x = 18 x = 3 The number is 3.
33) A man is nine times as old as his so. In nine years he will be only three times as old as his son. How old are each now? x: age of son 9x: age of man 9x + 9 = 3(x + 9) 9x + 9 = 3x + 27 6x = 18 x = 3 9x = 27 man: 27 yrs old son: 3 yrs old
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A man is nine times as old as his so. In nine years he will be only three times as old as his son. How old are each now?
Find a number which decreased by 18 is 5 times its opposite.
3(x+3)-2x=4(x-1)
4x-3=3(x+1)
2(ax-b)=cx+3d
Worksheet_01
Delete15) 4x-3=3(x+1)
4x - 3 = 3x + 3
x = 6
16) 3(x+3)-2x=4(x-1)
3x + 9 - 2x = 4x - 4
x + 9 = 4x - 4
13 = 3x
x = 13/3
24) 2(ax-b)=cx+3d
2ax - 2b = cx + 3d
2ax - cx = 2b + 3d
(2a - c)x = 2b + 3d
x = (2b + 3d)/(2a - c)
31) Find a number which decreased by 18 is 5 times its opposite.
x: the number
x - 18 = 5 (-x)
6x = 18
x = 3
The number is 3.
33) A man is nine times as old as his so. In nine years he will be only three times as old as his son. How old are each now?
x: age of son
9x: age of man
9x + 9 = 3(x + 9)
9x + 9 = 3x + 27
6x = 18
x = 3
9x = 27
man: 27 yrs old
son: 3 yrs old