Question

solve the system of equations by substitution -6x+7y=23, -5x+y=24

Answer 1

Answer:

x = -5,  y = -1

Step-by-step explanation:

You're given 2 equations:

-6x + 7y = 23

-5x + y = 24

you choose the equation that is easier to isolate a single variable to use as your substitution. I chose -5x + y = 24 because the 'y' is already by itself. Now solve for 'y'.

-5x + y = 24

y = 24 + 5x

Use this y-value to substitute into your other equation

-6x + 7y = 23

-6x + 7(24 + 5x) = 23

-6x + 168 + 35x = 23

29x = 23 - 168

29x = -145

x = -5

We found the value of 'x', so plug it back in to any of the two given equation to solve for y.

-5x + y = 24

-5(-5) + y = 24

25 + y = 24

y = 24 - 25

y = -1

Answer 2

Answer:

(-5,-1)

Step-by-step explanation:

First you must get a variable on one side alone. For example I done Y on the 2nd one. So to move it, you would take the 5x and move/add to the other side so Y=5x+24.

Then the substitution comes in. So you take

-6x+7(5x+24)=23 so you would plug in what Y equals. Then after you distribute the seven you would combine like terms. Then you take and move/subtract 168 from 23 which equals -145. Then you would divide by the number attached to the variable which is 29, therefore giving you x=-5

Then to get Y you simply plug what X equals into the X space.

Y=5(-5)+24

Y= -25+24

Y=-1