Tuesday, October 7, 2014

How much the x and y value in this equation below? 3x-7=4 2x-2y=8no

3x - 7 = 4    ...  (1)


2x - 2y = 8  ...  (2)


In equation transferring the number - 7 to the left hand side of equation we get:
3x = 4 + 7 = 11


Therefore: x = 11/3


Substituting this value of x in equation (2) we get:


2*(11/3) - 2y = 8


Therefore: -2y = 8 - 22/3 = (24 - 22)/3 = 2/3


Therefore: y = (50/3)/(-2) = -1/3.


Answer:


x = 11/3,  y = -1/3.


The above solution solution is give based on equation as these are given. It appears in the first equation the second term is given as -7 instead of -y. I am giving below also a solution based on the modified equations>


3x - y = 4    ...  (1)


2x - 2y = 8  ...  (2)


Multiplying both sides of equation (1) we get:


6x - 2y = 8   ...   (3)


Subtracting equation (2) from equation (3) we get:


6x - 2x  - 2y + 2y = 8 - 8


Therefore: 4x = 0


Therefore: x = 0


Substituting this value of x in equation (1) we get


3*0 - y = 4


Therefore: -y = 4


Or: y = -4


Answer for modified equations:


x = 0,  y = -4.

No comments:

Post a Comment