The sum of two integers is 38. Four times the smaller is 65 less than three times the larger. Find the numbers.
(practice questions for exam =| )
(practice questions for exam =| )
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let the two integers be X and Y
given,
X+Y=38................(1)
let X be the smaller of the two
then,
4X=3Y-65
4X-3Y=-65............(2)
SOLVE 1 AND 2
multiply (1)by 3
3X+3Y=114
4X-3Y=-65
SO, 7X=49
X=7
from 1,
X+Y=38
7+Y=38
Y=31
given,
X+Y=38................(1)
let X be the smaller of the two
then,
4X=3Y-65
4X-3Y=-65............(2)
SOLVE 1 AND 2
multiply (1)by 3
3X+3Y=114
4X-3Y=-65
SO, 7X=49
X=7
from 1,
X+Y=38
7+Y=38
Y=31
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One Number = x
Other Number = y
x + y = 38, or
y = 38 - x..................Eq. 1
4x = 3y - 65..............Eq. 2
Sub 38 - x from Eq. 1 for y in Eq. 2:
4x = 3(38 - x) - 65
4x = 114 - 3x - 65
4x + 3x = 114 - 65
7x = 49
x = 49 / 7
x = 7
and
y = 38 - 7
y = 31
The numbers are 7 and 31.
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Other Number = y
x + y = 38, or
y = 38 - x..................Eq. 1
4x = 3y - 65..............Eq. 2
Sub 38 - x from Eq. 1 for y in Eq. 2:
4x = 3(38 - x) - 65
4x = 114 - 3x - 65
4x + 3x = 114 - 65
7x = 49
x = 49 / 7
x = 7
and
y = 38 - 7
y = 31
The numbers are 7 and 31.
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x + y =38
4x + 65 = 3y
Plug and chug...
4x + 65 = 3(38-x)
4x + 65 = 114 - 3x
7x = 49
x = 7
y = 31
4x + 65 = 3y
Plug and chug...
4x + 65 = 3(38-x)
4x + 65 = 114 - 3x
7x = 49
x = 7
y = 31