Question

A system of equations is shown below.

-3x + 7y = -16
-9x + 5y = 16

Part A: Create an equivalent system of equations by replacing one equation with the sum of that equation and a multiple of the other. Show the steps to do this. (6 points)

Part B: Show that the equivalent system has the same solution as the original system of equations. (4 points)

Answer 1

@ranga can you please help me?

Answer 2

-3x + 7y = -16 ---- (1)
-9x + 5y = 16 ---- (2)
"Replace one equation with the sum of that equation and a multiple of the other."

Let us replace (2) by adding (2) to two times (1):
2 times (1): -6x + 14y = -32
Add (2): -9x + 5y = 16
--------------------
-15x + 19y = -16

So the second pair of equations are:
-3x + 7y = -16 ---- (1)
-15x + 19y = -16 ----- (3)


For B)
Solve (1) and (2) for x,y
Solve (1) and (3) for x,y

Show they are the same solutions.

Answer 3

(1) (2) (3) ??? what do these mean??

Answer 4

@ranga

Answer 5

Sorry I get it now! Thank you so so much!!!