Question 305366
Let x = the 10's digit
Let y = the units digit
Let z = the digits after 8 has been subtracted
10x + y = "the number"
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Write an equation for each statement:
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For a two digit numbers it's digit in the ten’s place is twice the digit in the unit’s place.
x = 2y
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When 8 is subtracted from the number; digits at both places are equal.
10x + y - 8 = 10z + z
Replace x with 2y
10(2y) + y = 11z + 8
20y + y = 11z + 8
21y = 11z + 8
y = {{{11/21}}}z + {{{8/21}}}
The only value for z that gives an integer value for y, is 5
y = {{{11/21}}}(5) + {{{8/21}}}
y = {{{55/21}}}z + {{{8/21}}}
y = {{{63/21}}}z 
y = 3
then
x = 2(3)
x = 6
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The number = 63
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Check: 63 - 8 = 55