dannyguz
contestada

Two Times a number added to another number is 25. three time the first number minus the other number is 20. find the numbers

Respuesta :

2x+y=25
3x-y=20
solve by adding these two equations together
2x+3x=5x
y-y=0
25+20=45
you get left with
5x=45
divide both sides by 5
x=9
then plug x=9 into one of the 1st equations to solve for y
2(9)+y=25
18+y=25
subtract
y=7

so your numbers are 9 and 7
simplylailah
Equation 1: 2x + y = 25
-Subtract 'y' (or 1) to both sides
2x + 1 - 1 = 25 - 1
2x = 24
-Divide '2' to both sides
2x/2 = 24/2
x = 12 (I think)
Equation 2: 3y - x = 20
-Add 'x' (or 1) to both sides
3y - 1 + 1 = 20 + 1
3y = 21
-Divide '3' to both sides
3y/3 = 21/3
y = 7

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