Question

Can you please advise if I worked this problem correctly:

11 + x = -15y

2x - 5y = 48

15y = 11+x
y = .73 + 15x

2x (.73 + 15X) - 48
2x -3.65 -75x = 48
-73x - 3.65 = 48
x = 51.65
x = -.70

Answer 1

check it yourself like this:
11 + (-.7) = -15(y) ?????

I think x = 19 and y = -2

http://www.idomaths.com/gauss_jordan.php
with
+1 15 -11
+2 -5 +48

Answer 2

Rewrite your equations:

11 + x = - 15 y Subtract 11 to both sides

11 + x - 11 = - 15 y - 11

x = - 15 y - 11 Add 15 y to both sides

x + 15 y = - 15y - 11 + 15 y

x + 15 y = - 11



2 x - 5 y = 48 Multiply both sides by 3

2 x * 3 - 5 y * 3 = 48 * 3

6 x - 15 y = 144


Now your system become:

x + 15 y = - 11

6 x - 15 y = 144
________________


x + 15 y = - 11
+
6 x - 15 y = 144
________________

x + 6x + 15 y - 15 y = - 11 + 144

7 x = 133 Divide both sides by 7

x = 133 / 7

x = 19


Replace this value in equation:

11 + x = - 15y


11 + 19 = - 15 y

30 = - 15 y Divide both sides by - 15

30 / - 15 = y

- 2 = y

y = - 2


Solution:

x = 19 and y = - 2



Proof:

11 + x = -15 y

11 + 19 = - 15 * ( - 2 )

30 = 30



2 x - 5 y = 48

2 * 19 - 5 * ( - 2 ) = 48

38 + 10 = 48

48 = 48