Question

Alex’s age take away Annie’s age and you will get 12. Alex’s age is twice Annie’s plus three

Answer 1

Explanation:

Let's give their ages variables. Alex will be x and Annie will be y. You can solve via substitution.

x-y=12

x=2y+3

You solve the first equation by just moving the x to the right and dividing by -1, giving you y=x-12. After this, you substitute x-12 for y in the second equation.

x=2(x-12)+3

x=2x-24+3

x=2x-21

After this step, you'll wanna subtract 2x from both sides

x-2x=2x-21-2x

-x=-21

Then you want to divide by -1

x=21

Alex is 21, so we plug that back into our first equation.

21-y=12

-y=-9

(-y=-9)/1

y=9

When you've done that, you get Alex is 21 years old and Annie is 9.

(21,9)

Answer 2

Answer:Alex is 21 years old.

Annie is 9 years old.

Explanation:

Let x represent Alex's age.

Let y represent Annie's age.

Alex’s age take away Annie’s age and you will get 12. This means that

x - y = 12

x = 12 + y - - - - - - - - - - - -1

Alex’s age is twice Annie’s plus three. This means that

x = 2y + 3 - - - - - - - - - - - - -2

Substituting equation 1 into equation 2, it becomes

12 + y = 2y + 3

2y - y = 12 - 3

y = 9

Substituting y = 9 into equation 1, it becomes

x = 12 + 9 = 21