Find the value of a-b+c+d 2x+8y=7 4x-2y=9

The value of a - b + c + d = -4

Step-by-step explanation:

* Lets explain the linear equation

- The linear equation is the equation that represented graphically

  by a line

- The general form of its equation is ax + by = c

- The slope of the line is -a/b and the y-intercept of the line is c/a,

  where a is the coefficient of x , b is the coefficient of y and c is the

  numerical term

∵ We have two linear equation in the problem

∴ Their general form is ax + by = e , cx + dy = f

∵ The equation are 2x + 8y = 7 and 4x - 2y = 9

- By comparing the two equations with their general forms

∴ a = 2 , b = 8 , c = 4 , d = -2

- Now we can find the value of a - b + c + d

∵ a = 2 , b  = 8 , c = 4 , d = -2

∴ a - b + c + d = 2 - 8 + 4 + (-2) = 2 - 8 + 4 - 2 = -4

* The value of a - b + c + d = -4