You can
put this solution on YOUR website!Let m = Maya's age now
Let d = David's age now
;
Write an equation for each statement;
"In 15 years, Maya will be twice as old as David is now."
m + 15 = 2d
:
"In 15 years, David will be as old as Maya will be in 10 years from now."
d + 15 = m + 10
d = m + 10 - 15
d = m - 5
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how old are they now?
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Substitute (m-5) for d in the 1st equation
m + 15 = 2(m-5)
m + 15 = 2m - 10
15 + 10 = 2m - m
m = 25 yrs is m's present age
:
d = m - 5
d = 25 - 5
d = 20 is d's present age
;
:
Check solutions in the statement:
"In 15 years, David will be as old as Maya will be in 10 years from now."
d + 15 = m + 10
20 + 15 = 25 + 10; confirms our solutions
