Question

Use the substitution method to solve the system of equations. choose the correct ordered pair

Answer 1

Answer:

x = 3

y = 21

(3,21) and if u want slope it will be 7 :D

Step-by-step explanation:

y = 10x - 9

y = x + 18

1. Substitute for the y

10x - 9 = x + 18

2. Add 9 onto both sides

10x - 9 + 9 = x + 18 + 9

10x = x + 27

3. Subtract x on both sides

10x -x = x - x+ 27

9x = 27

4. Divide by 9 on both sides

9x/9= 27/9

x = 3

__________________________________________________________

Now that you have x, substitute that into one of the equations

y = x + 18

y = 3 + 18

y = 21

or  

y = 10x - 9

y = 10(3) - 9

y = 30 - 9

y = 21

there both the same

__________________________________________________________

x = 3

y = 21

Hope this helped!

Answer 2

Answer:

x +18 = 10x -9 (since they both = y, set them equal to each other. )

-9x +18 = -9 (subtract 10x from both sides, then subtract 18 from both sides)

-9x = -27 (divide both sides by -9 to isolate x)

x= 3 (take this and plug it into one of the equations to solve for y)

y = x +18 (i choose this one)

y = 3+18 (add)

y = 21 (take this and x and make a point and that's your answer)

(3,21) or C

Step-by-step explanation:

I hope this helps :)