# Math

posted by Tyler

How to solve the two formulas for x+y=21 3x+4y=21

1. Vanessa

you can use a substraction-or-addition method or substitude method.
So...
x+y=21 you multiply both side by 3 3x+3y=63
3x+4y=21
---------
then you eliminate one variable
you use the subtraction method
-y=42
y=-42
then you solve for x by substituting the y
x+(-42)=21
x=63

2. brandon

i need to know how to turn 48.25 into a fration in simpilist forn

3. Reiny

48.25 =4825/100 = 193/4 = 48 1/4

or just realize that .25 = 1/4
so 48.25 = 48 1/4

Please don't post a question as part of a previous thread, start a new topic
That way you will have a much better chance at a tutor looking at it.

4. Reiny

48.25 =4825/100 = 193/4 = 48 1/4

or just realize that .25 = 1/4
so 48.25 = 48 1/4

Please don't post a question as part of a previous thread, start a new topic
That way you will have a much better chance at a tutor looking at it.

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