Question

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

y = 3x + 2
y = x + 12

A. (0, 12)
B. (3, 2)
C. (5, 17)
D. (0, 2)

Answer 1

Hey!

Answer 2

Do you know what the substitution method is?

Answer 3

eh kind of.... But if you could refresh that would be great! :D

Answer 4

Umm, I'll take that as a no

It's basically solving for a variable, then inputting what you got for it.

y = 3x + 2
y = x + 12

We already have y solved for, so lets input in for y

3x + 2 = x + 12

Subtract 2 from both sides

3x = x + 10

Subtract x from both sides

2x = 10

Divide both sides by 2

x = 5

Answer 5

Notice how they both have y = ______ . That means that both equations equal y. Thus meaning that both equations equal each other. So we can put them as equaling each other to solve for x.

Answer 6

So now we have x = 5

Lets put in 5 for x and solve for y.

y = x + 12

y = 5 + 12

y = 17

Answer 7

Now lets CHECK our ANSWER by inputting in our answers to see if we get it correct.

Remember
x = 5
y = 17

y = 3x + 2

17 = 3(5) + 2

17 = 15 + 2

17 = 17

That's correct, now lets check the other one.

y = x + 12

17 = 5 + 12

17 = 17

That's correct too!

So now we can so for sure that:

x = 5
and
y = 17

Answer 8

Ok so then it would be (5,17)? So C would be the answer correct?

Answer 9

Yep.

Remember how you solve for slope and all that. Coordinates are put into the format of (x,y)

So yeah, (5,17) is correct

Answer 10

If you need any further help with anything, just link me by posting @ShadowLegendX in your question ;P

Answer 11

Ok!!! For sure!