Question

Solve the system of Equations
y = 3x + 2
x - 2y = 10
Please someone help I am a little confused

Answer 1

Do you want to do substitution or elimination?

Answer 2

It doesn't specify it just reads to solve the system of equations. I am sorry

Answer 3

Well, there are different ways to solve it, graphing, substitution or elimination

Answer 4

for this one, i'll do substitution because it's easier

Answer 5

sounds good. just not to sure how to do that though but easier the better

Answer 6

Since the first equation already tells you that y = 3x+2, plug in the y equation into the second equation. x -2 (3x+2)=10

Answer 7

So I basically shoved the first equation into a variable for the 2nd equation

Answer 8

y = 3x + 2
x - 2y = 10

x-2(3x+2) = 10
x-6x -4 = 10
-5x - 4 = 10
-5x = 14
x = (14/-5)

y = 3(14/-5) + 2
y = -6.4

---Heres the work for substitution.

Answer 9

Plug the answers for each variable into the equations above, if the 2 equations presented above match, then it is correct.

Answer 10

yea. that is the way to check the work :)

3( 14/-5) + 2 = ???? hopefully -6.4
and
(14/-5) - 2(-6.4) = ???? hopefully 10

Answer 11

I am lost

Answer 12

3(14/-5)+2 = y. 3(14/-5) = -6.4, so y = -6.4. So now use the second equation and plug in those variables (14/-5)-(2 times -6.4), and if it equals 10, then it is correct

Answer 13

y = 3x + 2 (Given)
x - 2y = 10 (Given)

x-2(3x+2) = 10 (substitued Y from first equation into second)
x-6x -4 = 10 (solving for x)
-5x - 4 = 10 (combined x terms)
-5x = 14 (add 4 both sides)
x = (14/-5) (divide by neg 5)

y = 3(14/-5) + 2 (now I know what x is, substitute that back in the other equation)
y = -6.4 (solved by using arithmetic)

Answer 14

Yes, you are correct for the variables and the work looks good! =)

Answer 15

NOTE Adjustment to this line: x-6x -4 = 10 (solving for x: used the distribution property to simply into like terms)

Answer 16

Thank you so much for all of your help I understand it now Thanks again

Answer 17

Np, also if you're really sick of doing substitution or elimination, you can just use geoalgebra( a free graphing system) to graph and find where the line intersects, the intersection point will represent the (x,y) values. ( not good for decimals tho)

Answer 18

Besides that, np and goodluck =)

Answer 19

Is the concept clear for you? (I can elaborate on what @Schen421 said if you'd like)