Question

Can you substitute this 3x-4y=-1 and x+y=5

Answer 1

x=(4y-1)/3

(4y-1)/3+y=5

(y-1)/3+y=5/4

2y-1=15/4

2y=4

y=2

x=7/3

Answer 2

one has a slope of 3/4 the other a slope of -1; to they do cross at a point .... thats always a good start

Answer 3

3x -4y = -1
x + y = 5 (-3)


3x -4y = - 1
-3x -3y = -15
--------------
-7y = -16

y = 16/7 ... if i did it right

Answer 4

3x -4y = -1
x + y = 5 (-4)


3x -4y = -1
4x +4y = 20
-----------
7x = 19

x = 19/7 perhaps ?

Answer 5

and by (-4) i mean (+4) :)

Answer 6

then where did I go wrong?

Answer 7

my first guess? typing in the reply box ;)

Answer 8

I need it in algebraic method..

Answer 9

that is in "algebraic" method.

Answer 10

Linear?

Answer 11

3x-4y=-1

x = (4y -1)/3....

I did not use "substitution"; but i used algebraic methods

Answer 12

I need substitution :(

Answer 13

(4y-1)/3+y=5 ; *3

4y -1 +3y = 15 ; combine like terms

7y - 1 = 15 ; +1

7y = 16 ; /7

y = 16/7

Answer 14

Llort: (y-1)/3+y=5/4 this is fictitious :)

Answer 15

if you "need" substitution; then substitute ... the answers are the same regardless

Answer 16

ohhh, thanks, I forgot PEMDAS... or BEDMAS, whatever you call it.

Answer 17

id have picked the simpler equation to determine the substitutes ... but its all good :)