7x+2y=4, 6x-2y=6

Question

Find the solution of equations if any. Please explain

Answer 1

7x+2y=4

6x-2y=6

 

Add the equations: left to left and right to right:

 

13x + 0 = 10

 

x = 10/13

 

7x+2y=4

 

y = (4-7(10/13))/2

 

y = (4 - 70/13)/2

 

y = 2 - 35/13

 

y = 2*13/13 - 35/13

 

y = (26 - 35)/13

 

y = -9/13

 

Solution is (10/13,-9/13)

check:

7(10/13)+2(-9/13) =? 4
70/13-18/13 =? 4
52/13 = 4 √

6(10/13)-2(-9/13) =? 6
60/13+18/13 =? 6
78/13 = 6 √