Question

HELP! Solve the following system of equations. Enter the y-coordinate of the solution. Round your answer to the nearest tenth.

5x+2y=21
-2x+6y=-34

Answer 1

How do you propose to solve these?

Personally, I would multiply the first by 2 and the second by 5 and then add them.

Answer 2

x=5.70
y=-3.76

Answer 3

I dont know how to go about solving this. This is like foreign to me @tkhunny :(

Answer 4

Did you do what I said?

Answer 5

@giligails so if its asking for just the y coordinate and to round to the nearest tenth would it be 4?

Answer 6

@tkhunny which numbers should i be multiplying?

Answer 7

Multiply the equations so either the coefficient of x or y are the same, the eliminate one variable and solve. Place value in initial equation to fine other variable.

Answer 8

5x+2y=21
-2x+6y=-34

Multiply the first by 2

10x+4y=42

Multiply the second by 5

-10x+30y=-170

Now add the two equations.

10x - 10x = ??
4y + 30y = ??
42 - 170 = ??

Answer 9

first 2y=21-5x
therefore -2x+3(21-5x)=-34
-2x-15x=-34-63
-17x=-97
x=97/17
2y=21-97*5/17
21-28.529=2y
2y=-7.529
y=-3.764

Answer 10

Now that I think about it, I would have left the first alone and multiplied the second by 5/2. No matter. It will all work out if no error is made.

Answer 11

@tkhunny thank you, so how would those steps be broken down? if you dont mind

Answer 12

@giligails so the answer is simply -3.764? is that including rounding it up to the nearest tenth?

Answer 13

Not a good question. Those ARE the steps broken down.

Did you do the additions? There are three of them there for you.

Answer 14

I got 0, 34y and -128. but i dont know how which one would be the answer @tkhunny

Answer 15

You are adding equations. You should be left with an equation.

0 + 34y = -128

or just

34y = -128

Solve for y.