Question

[6.02] Solve the following system.
y = x + 3
2x + y = 9

(2, 5)

(5, 2)

(−2, 5)

(2, −5)

Answer 1

Do you know how to solve simultaneously?

Answer 2

i'm just very confused with this whole lesson

Answer 3

Okay - ill go through it with you
So, you have ben given two equations.

Answer 4

We want to know what x is so that it satisfies both equations.

Answer 5

Okay

Answer 6

To do this, there is a method of subtitution.

Answer 7

You have been given the equation (y= x+3)
You have two unknows - x and y

Answer 8

The first step is to substitute (y= x+3) into the the equation 2x+y=9

So you get:
2x+y =9

2x+(x+3)=9


Are you able to solve this?

Answer 9

Do I solve the second one only?

Answer 10

Yes, solve the second one

Answer 11

HINT: 2x + (x+3) = 9
3x +3 = 9