Solve -3x plus 4y equals 12?

Answer 1

-3x + 4y = 12

Temporary value of y:

4y = 3x + 12

y = (3x + 12) / 4

Substituting y:

-3x + 4 [(3x+12) / 4] = 12

-3x + 12x + 48 = 12

-3x + 12x = 12 - 48

9x = 12 - 48

9x = -36

x = -36 / 9

x = -4

Subtituting x to get the final value of y:

-3(-4) + 4y = 12

12 + 4y = 12

4y = 12 - 12

4y = 0

y = 0

Final answer:

x = -4

y = 0

Check:

-3x + 4y = 12

-3(-4) + 4(0) = 12

12 + 0 = 12

12 = 12

Solution 2:

-3x + 4y = 12

Temporay value of x:

3x = 4y - 12

x = (4y - 12) / 3

Substituting x to get the value of y:

3[(4y - 12) / 3] + 4y = 12

12y - 36 + 4y = 12

16y = 12 + 36

16y = 48

y = 48 / 16

y = 3

Substituting y to get the value of x:

-3x + 4(3) = 12

-3x + 12 = 12

-3x = 12 - 12

x = 0

Final Answer:

x = 0

y = 3

Check:

-3(0) + 4(3) = 12

12 = 12