Question

Solve system by elimination
6.
2x + 5y = 14
4x + 2 y = -4
​

Answer 1

Step by step:
Multiply the first one by -2 to be able to eliminate the x’s
-4x-10y=-28
Add them
-4x-10y=-28
4x+2y=-4
——————-
X’s cancel out your left with
-8y=-32
Divide by -8 to get y alone
Y= 4
Plug in for y to get x
4x+2(4)=-4
4x+8=-4
-8 -8
————-
4x=-12
x=-3
(-3,4)

Answer 2

x=−3 and y=4

Explanation:

Multiply the first equation by -2,and multiply the second equation by 1.

−2(2x+5y=14)

1(4x+2y=−4)

Becomes:

−4x−10y=−28

4x+2y=−4

Add these equations to eliminate x:

−8y=−32

Then solve−8y=−32for y:

−8y=−32

−8y

−8

=

−32

−8

(Divide both sides by -8)

y=4

Now that we've found y let's plug it back in to solve for x.

Write down an original equation:

2x+5y=14

Substitute4foryin2x+5y=14:

2x+(5)(4)=14

2x+20=14(Simplify both sides of the equation)

2x+20+−20=14+−20(Add -20 to both sides)

2x=−6

2x

2

=

−6

2

(Divide both sides by 2)

x=−3