Question 542134
Let L = Luc's present age
Let K = Kate's present age
:
Write an equation for each statement:
:
"LUC IS THREE YEARS MORE THAN TWICE KATE'S AGE.
L = 2K + 3
:
"FOUR YEARS AGO TH SUM OF THEIR AGES WAS 25."
L-4 + K-4 = 25
L + K - 8 = 25
L + K = 25 + 8
L + K = 33
From the 1st statement, replace L with (2K+3)
2K + 3 + K = 33
3K = 33 - 3
3K = 30
K = 30/3
K = 10 yrs is Kate's present age
:
Find L
L = 2(10) + 3
L = 23 is Luc's present age
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You can check these solutions in the statement:
"FOUR YEARS AGO TH SUM OF THEIR AGES WAS 25."
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:
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2. ??
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3) {{{3/5}}}N - 5 = 5N + 39
add 5 to both sides
{{{3/5}}}N = 5N + 39 + 5
{{{3/5}}}N = 5N + 44
Multiply both sides by 5 to get rid of the denominator
3N = 5(5N + 44)
3N = 25N + 220
3N - 25N = 220
-22N = 220
Divide both sides by -22
N = 220/-22
N = -10
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You can check this solution in the original equation