can u solve this simultaneous equation?(by elimination)?

Question

5x+2y=16
-3x+4y=-7

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Answer 1

Yes -- I can.

1. Multiply the top equation by 2. You get:

10x+4y=32
-3x+4y=-7

2. Now suptract the second from the first:

13x = 39

3. Divide both sides by 13

x = 3

4. Plug this into any equation.

5*3+2y=16

2y = 1

y = 0.5

Answer 2

Start by looking to make the coefficients of one variable additive inverses:

2y can be multiplied by -2 to get -4y; -4y + 4y=0

Always remember to multiply EVERYTHING in the top equation by -2 when you do this.
-2 [ 5x + 2y =16]
-10x -4y = -32

Add the full two equations together:

(-10x - 4y = -32)
+ (-3x + 4y = -7)
---------------------------
-13 x + 0 = -39

(-13x)/-13x = -39/-13
x=3

Plug your x back into either of the equations:
5(3) +2y =16
15 + 2y =16
2y=16-15
2y=1
y=1/2

or

-3(3) + 4y = -7
-9 + 4y = -7
4y = -7 + 9
4y = 2
y= 2/4 or 1/2 reduced

x=3, y=1/2

Answer 3

1. multiply equation 1 through by -2 giving you:
-10x -4y = -32
- 3x+4y= - 7
2. add together and get
-13x= -39 x=3

3. substitute this and get 15+2y=16; 2y=1; y=1/2
4. 5(3)+2(1/2)=1 and -3(3)+4(1/2)= -7

Answer 4

5x + 2y = 16
-3x + 4y = -7

Multiply the first equation by -2

-10x - 4y = -32
-3x + 4y = -7

Add both equations

-13x + 0y = -39

Gives us
x = 3

Substitute 3 for x in either of your given equations to solve for y

5(3) + 2y = 16

15 + 2y = 16

2y = 1

Y = 1/2
.

Answer 5

5x+2y=16 -------- (1)
-3x+4y=-7 -------- (2)

(1) x 2
10x + 4y = 32 ------- (3)

(3) - (2)
13x = 39
x = 39/13 = 3
when x = 3 be replace it (2)
-3(3) + 4y= -7
-9 + 4y = -7
4y = 9 -7
4y = 2
y = 1/2