how to solve this

Question

-4x-y=-1

-4x-5y=-5

solve by substitution

Answer 1

These kinds of problems may seem complex, but there's just a little trick you can use to make this easier. What you're going to do is pick a variable out of the ones in your equation, let's say you pick y. You're going to take one of your equations, -4x-y=1, and solve for y, meaning that by the end you'll have something like this: y = -4x -1. Now you have what y is equal to in terms of x! Next step is to plug that y value into the second equation in the place of the original y, like this: -4x-5(-4x-1)=-5 and simplify from there! Then you have what your x value equals as an actual number. You can then plug that in to either equation and solve for y again to get the actual number that y is equal to! Check your answers by plugging those values back into your original equations to see fi you get the same answers on both sides of the equals sign.

Answer 2

From first equation, y = 1 - 4x. Then substitute in the 2nd equation.

-4x - 5(1 - 4x) = -5

16x - 5 = -5

x = 0

Plug back into the first equation, y = 1 - 0 = 1

Answer 3

Put one of the two equations in the form y = ax +b

The first one is simpler.

-4x-y=-1

Add one to both sides

-4x-y+1 = 0

Add y to both sides

-4x+1 = y

Now substitute for y in the second equation

-4x-5y=-5

-4x-5(-4x+1)=-5

Then simplify for x

-4x+20x-5 =-5

Add 5 to both sides

16x = 0

which means x = 0

take either the first or the second equation substitute 0 for x and solve for y

-4(0)-y=-1

-y = -1

y=1

(0,1)

Answer 4

The first equation can be rewritten as

-4x = y - 1

In the second equation, substitute y - 1 in the place of the first "-4x".

Now you have

y - 1 - 5y = -5.