lets solve by substitution?

Question

2x + 4y = 9

-2x + y = 5

Answer 1

2x+4y=9
-2x+y=5

The first one solve for x:
2x+4y=9 <=>
2x=9-4y <=> (divide by 2)
x=4.5-2y

Replace in the second one:
-2*(4.5-2y)+y=5 <=>
-9+4y+y=5 <=> (we have 4y+y=5y)
5y=5+9 <=>
5y=14 <=>
y=14/5

Answer 2

i think u can solve this by elimination

2x+4y=9
-2x+y=5

2x-2x cancel out and u add 4y and y and 9 and 5

that gives u 5y=14

then u solve

if u want to solve by substitution u hav to isolate y in the second equation
which gives u y=2x=5
now plug in that value for y into the first equation

Answer 3

4y = 9 - 2x
y = 5 + 2x ( because minus -2x is a positive value)

4(5 + 2x) = 9 - 2x

20 + 8x = 9 - 2x
10x = -11
x = -1.1

Answer 4

From the second equation, y = 5 + 2x.

Therefore:
2x + 4(5 + 2x) = 9
2x + 20 + 8x = 9
10x + 20 = 9
10x = -11
x = -1.1

y = 5 + 2x
y = 5 - 2.2
y = 2.8