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

@undeadknight26

Answer 2

help plz

Answer 3

if you multiply the first equation by -3 can cancel the x values... give it a try ;)

Answer 4

i dont really get what you mean

Answer 5

ok... one sec

Answer 6

k

Answer 7

disregard... I was setting up to solve the system of equations... but is actually asking something different

Answer 8

can you still help me?

Answer 9

ok... so according to part (a) you need to create a new systrem that involves a sum and a multiple of the other equation... in other words... we need to solve for one variable in terms of the other in one of the equations and plug in that value into the other equation

Answer 10

i still dont really get it

Answer 11

you mean i have to solve what x is for the first equation then plug in the x on the second equation?

Answer 12

lets solve the system first to see what the answer is

Answer 13

yes... that's right

Answer 14

but then you have to prove it to see if it is the same as the original equations so lets solve the system by elimination method

Answer 15

k

Answer 16

how do i solve it with elimination method?

Answer 17

can u multiply the first equation by -3? what do u get?

Answer 18

9x-21y=-48?

Answer 19

positive 48

Answer 20

oh yeah negative times negative is positive

Answer 21

now lets apply elimination method... one sec