Question

use the elimination method to solve the system
-4x+4y=-8
x-4y=-7
options
A-(3,5)
B-(5,3)
C-(-3,-5)
D-(-5,-3)
Please show work

Answer 1

-4x+4y=-8
x-4y=-7
----------
-3x=-15
x=5

Answer 2

how do u get the second part

Answer 3

what second part?

Answer 4

the second answer

Answer 5

you mean y-coordinate?

Answer 6

yea

Answer 7

I dont know whats the name of this method in english but thats what i use to solve:
x=-7+4y
-4(-7+4y)+4y=-8
28-16y+4y=-8
-12y=-8-28
y=-36/-12
y=3

Answer 8

(5,3)

Answer 9

x-4y=-7
as x=5,
5-4y=-7
-4y=-7-5
-4y=-12
y=3

Answer 10

thanks so much that was very helpful

Answer 11

-4x+4y = -8........(i)
x-4y = -7...........(ii)
add equation (i) and (ii)
-4x+x+4y-4y = -8-7
-3x = -15
x = 5
substituting x= 5 in (ii)
5+7 =4y
y = 12/4 = 3
(5,3)

Answer 12

@matias.mingo your method is substitution method as you substitute one variable in place of other.

Answer 13

you are correct sir