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Please help urgent easy question,just no 8

Please help urgent easy question,just no 8-example-1
User Turid
by
5.6k points

2 Answers

2 votes

Answer:

Ruby is 11. Tanya is 14.

Explanation:

Let Ruby's age eight years ago be x.

Tanya's age eight years ago = 2x.

Ruby's age now = x + 8

Tanya's age now = 2x + 8

Total age =
x+8+2x+8=25


3x+16=25

Subtract 16 from both sides:


3x+16-16=25-16


3x=9

Divide both sides by 3:


(3x)/(3) =(9)/(3)


x=3

Ruby's age now
=x+8=3+8=11

Tanya's age now
=2x+8=2(3)+8=6+8=14

User Fadila
by
5.5k points
7 votes

Answer:

Tanya is 14; Ruby is 11.

Explanation:

Let T represent Tanya's current age and let R represent Ruby's current age.

We know that their ages add up to 25. So:


T+R=25

8 years ago, Tanya was twice as old as Ruby. In other words, Tanya's current age minus 8 is the same as Ruby's current age minus 8 times 2. So:


T-8=2(R-8)

We have a system of equations. We can solve by substitution. From the first equation, subtract R from both sides:


T=25-R

Substitute this into the second equation:


(25-R)-8=2(R-8)

On the left, subtract. On the right, distribute:


17-R=2R-16

Add 16 to both sides. The right side cancels:


33-R=2R

Add R to both sides. The left cancels:


33=3R

Divide both sides by 3:


R=11

So, Ruby is currently 11 years old.

So, Tanya is currently 25-11 or 14 years old.

Check:

8 years ago, Ruby was 11-8 or 3 years old.

8 years ago, Tanya is 14-8 or 6 years old.

Tanya's age of 6 is 2 times Ruby's age of 3 so our answer is correct.

User AieshaDot
by
5.2k points