warmmuffin
Badges: 14
Rep:
?
#1
Report Thread starter 5 years ago
#1
How can i solve this?
x^2 + y^2 = 9
x+ y = 2
0
reply
Thorsas
Badges: 8
Rep:
?
#2
Report 5 years ago
#2
When you have two simultaneous equations and one is linear / simpler than the other (does not contain any squared terms) you can solve them by substitution.

Rearrange the simpler one to make x or y the subject, for example y = 2 - x (by subtracting x from both sides)

Can you see how that will help with the substitution method?
0
reply
username1560589
Badges: 20
Rep:
?
#3
Report 5 years ago
#3
(Original post by warmmuffin)
How can i solve this?
x^2 + y^2 = 9
x+ y = 2
Rearrange the bottom to get y = 2 - x, then substitute this into the top one.
Solve the resulting equation for x and then find the values of y.
0
reply
Chittesh14
Badges: 19
Rep:
?
#4
Report 5 years ago
#4
(Original post by warmmuffin)
How can i solve this?
x^2 + y^2 = 9
x+ y = 2
One is a simultaneous equation, the other is a linear equation.
What do you do, you rearrange the linear equation to get one of the values and substitute them into the simultaneous equation.

x^2 + y^2 = 9
x+ y = 2

If I, change this into y = 2 - x.
Therefore, substitute it into the linear equation and carry on, remember (2-x)^2 is not 4 - x^2, remember how to square something in brackets, looks like the difference of squares, but it is slightly different.


Posted from TSR Mobile
0
reply
X

Quick Reply

Attached files
Write a reply...
Reply
new posts
Back
to top
Latest
My Feed

See more of what you like on
The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

Personalise

Current uni students - are you thinking of dropping out of university?

Yes, I'm seriously considering dropping out (47)
15.93%
I'm not sure (8)
2.71%
No, I'm going to stick it out for now (101)
34.24%
I have already dropped out (4)
1.36%
I'm not a current university student (135)
45.76%

Watched Threads

View All