4x-7y=-23, y=2x-1

Question

i am trying to solve for system of linear equations

Answer 1

Since we already know that y = 2x - 1, we can substitution method to solve the system. Substitute the expression 2x - 1 in place of y in the other equation.

 

4x - 7y = -23

4x - 7(2x - 1) = -23 iff

4x - 14x + 7 = -23 iff

-10x + 7 = -23 iff

-10x = -30 iff

x = 3

 

Now plug in x = 3 into any of  the two equation to find y.

 

y = 2x - 1

y = 2(3) - 1 = 6 - 1 = 5

 

Thus the solution is (3, 5)

Answer 2

Thank you SOOO much Arang you are the best.