Question

Solve the system of equations: 10x+y=-18 0=5x+3y+4

Answer 1

So first you change the two equations into:
y = -18 - 10x and
-5x - 3y = 4

Then substitute y = -18 - 10x into the second equation for the y part

-5x - 3(-18 - 10x) = 4

Then simplify:

-5x + 54 + 30x = 4

Then put all the variables on one side while all the single numbers on the other:

-5x + 30x = 4 - 54

Then simplify:

25x = -50

Then divide 25 by both sides making it:

25x/25 = -50/25

Cancel out the 25’s on the left side… then your left with:

x = -50/25

so x = -2


And when you substitute x for -2 in either equation’s you get y as:

Work:

-5x - 3y = 4

-5(-2) -3y = 4

10 - 3y = 4
-10 -10

Cancel out the 10 on the left side
(since 10 -10 = 0)

Then your left with:

-3y = -6

Then divide -3 from both sides:

-3y/3 = -6/-3

The -3’s from the left side cancel out

So then y = 2 (since -6/-3 = 2)

THE ANSWER IS:

x = -2
y = 2