Question #def8e

2 Answers
Nov 22, 2017

Dakota is 48 years old and Patricia is 33 years old.

Explanation:

Let #d# represent the age of Dakota, and #p# the age of Patricia.

The first statement Dakota is 15 years older than Patricia tells us that:
#d = p + 15#

Our second statement in 9 years, the sum of their ages will be 99 tells us that:
#d + 9 + p + 9 = 99#
We can simplify this equation to give:
#d + p + 18 = 99#
#d + p = 81#
#d = 81 - p#

Substituting the second simplified equation into the first original equation:
#81 - p = p + 15#
Simplifying this:
#81 = 2p + 15#
#2p = 66#
#p = 33#

Finally, substituting #p = 33# into the original equation gives:
#d = 33 + 15#
#d = 48#

Check:

  • 48 is indeed 15 more than 33.
  • #33 + 9 = 42#
    #48 + 9 = 57#
    #57 + 42 = 99# So yes, the second statement is also true.

Conclusion:

Dakota is 48 years old and Patricia is 33 years old.

Nov 22, 2017

Pat is 33 and Dakota is 48

Explanation:

Let #x# equal the number of years in Pat's age now.

Pat's age now . . . . . . . #x# #larr# the number of years in Pat's age
15 years older . . . . . . . #x + 15# #larr# Dakota's age

In nine years, their ages will be:
Pat . . . . . . #x + 9# #larr# Pat's future age
Dakota . . .#x + 15 + 9# #larr# Dakota's future age

The sum of those future ages is 99.
[Pat's future age} "plus" [Dakota's future age] "equals" [ 99 }
[ . . . . #x + 9# . . . .]. . #+#.. [. . . #x + 15 + 9# . . . ]. . .#=#. . . [ 99 ]

#(x + 9) + (x + 15 + 9) = 99#
Solve for #x#, already defined as "Pat's age now."

1) Combine like terms
#2x + 33 = 99#

2) Subtract 33 from both sides to isolate the #2x# term
#2x = 66#

3) Divide both sides by 2 to isolate #x#, already defined as "Pat's age now."
#x = 33# #larr# answer for "Pat's age now"
Dakota is 15 years older, which is 48.

Answer:
Pat is 33 years old now.
Dakota's present age is 48
.........................

Check
Their ages in 9 years should add up to 99

In 9 years, Pat will be 42
In 9 years, Dakota will be 57
#42 + 57 = 99#

The total of those ages does equal 99
Check!