(Solve algebraically) One number is 3 more than twice the other number.
If the sum of the two numbers is 21, find the two numbers.
(Use a comma to separate answers as needed)

Question

(Solve algebraically) One number is 3 more than twice the other number. 
If the sum of the two numbers is 21, find the two numbers.
(Use a comma to separate answers as needed)

3psilon · Answer

So in this problem you are given two unknowns s o you will need 2 equations to solve

3psilon · Answer

one number we will call x the other number we will call y

3psilon · Answer

x = 3+2y
and
x+y=21

3psilon · Answer

So we can use x=3+2y  and plug it into the x+y =21 equation

3psilon · Answer

(3+2y)+y = 21

3psilon · Answer

3+3y=21
3y=18
y=6

3psilon · Answer

And now we have y so just plug it into the x+y= 21 formula again to find x :)

anonymous · Answer

got it! thank you very much!

3psilon · Answer

if you have any more questions about feel free to ask