209k views
3 votes
If someone could work out the first half of the problem and explain that would be great!

If someone could work out the first half of the problem and explain that would be-example-1
User MachineElf
by
8.1k points

2 Answers

4 votes

Answer:

x = -5

y = -5

Explanation:

If you multiply the top equation by negative 2, you can add it to the bottom equation and cancel out the x:

-2(-x + 5y = -20) --> 2x - 10y = 40

Add this to the bottom equation top to bottom:

2x - 10y = 40

-2x + 4y = -10

You get:

-6y = 30

Then solve for y:

y = -5

Plug this back in for either equation and solve for x:

-x + 5(-5) = -20

-x -25 = -20

-x = 5

x = -5

Your answers are:

x = -5

y = -5

User Filimonov
by
7.8k points
3 votes

Answer:

x =-5

y = -5

Explanation:

-x + 5y = -20 ----------1

-2x + 4y = -10 ---------2

Multiply eqn 1 by 2 and eqn 2 by 1

This is done to make coefficients of x in both equations the same so that x can be eliminated

-2x + 10y = -40

-2x + 4y = -10

Subtracting

6y = -30

y = -5

Substitute y = -5 in eqn 1

-x+5×-5=-20

-x - 25= -20

-x = -20+25 = 5

x = -5

User Gakio
by
7.5k points