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Solve the system of equations.

x+y+z=10
5x+3y=14
x−2y+z=2.5

PLZ HELP!!!!!!!!!!

User Reming Hsu
by
4.0k points

1 Answer

3 votes

Answer:

y=3,x=1.3,z=6.2 :)

Explanation:

y=3,x=1.3,z=6.2 :)

So, we have:

: x+y+z=10 [equation 1]

: 5x+3y=14 [equation 2]

: x−2y+z=2.5 [equation3]

(I'm going to assume that you know how to solve equations with 2 variables)

1. eliminate a variable to get 2 variables

Let's reverse equation 2:

-x+2y-z= -2.5

and take equation 1, to try to eliminate "z"

x+y+z=10

add up the 2 equations to get:

3y=7.5

and solve to get

y=2.5

2. substitute what we already solved into another equation

Luckily, equation 2 only has 2 variables, and one is y, so we can sub it in.

5x+3y=14 --> 3x+3(7.5)=14

solve to get

x=1.3

3. Substitute both of our variables in to get the final variable: z

Let's take the first equation.

x+y+z=10 --> 1.3+2.5+z=10

solve to get

z=6.2

I hope this helps you!

User DrStrangepork
by
4.0k points