Question

solve the equation step by step with the graph x+y=7,3x-y=7;​

Answer 1

Solution:

x + y = 7 ... Eq.1

3x - y = 7 ... Eq.2

Simultaneous equations by substitution or elimination method

Use elimination method:

Add eq.1 and eq.2 to eliminate y

x + y = 7
+
3x - y = 7

4x = 14

x = 14/4 = 7/2

Use eq.1 to solve for y by substituting the value of x

x + y = 7

7/2 + y = 7

y = 7 - 7/2 = 7/2

Therefore
x = 7/2 or 3.5 and y = 7/2 = 3.5

Hope this will be helpful to you

See the picture graph below

x + y = 7 ... (red)

3x - y = 7 ... (blue)