We use cookies to personalise content and advertisements and to analyse access to our website. Furthermore, our partners for online advertising receive pseudonymised information about your use of our website. cookie policy and privacy policy.
 
+0  
 
0
264
2
avatar+594 

Solve the system of equations. Show your work.

y = x- 3x + 4 

x + y = 4

 

Answer:

 Feb 27, 2018
 #1
avatar+102905 
+2

y = x^2 -3x + 4      (1)

x + y  = 4  ⇒   y  = 4 - x    (2)

 

Sub (2)  into (1)

 

4 - x  =  x^2  - 3x + 4       subtract 4 from both sides

 

-x = x^2 - 3x       add x to both sides

 

x^2 - 2x  = 0   factor

 

x( x - 2)  =  0

 

Set each factor to 0 and solve for x and we get that

 

x =  0   or x  = 2

 

When x = 0.....y  =  4 - 0  =    4      ⇒   (0, 4)

 

When x  =  2.....y  =  4 -  2   =  2  ⇒    (2 , 2)

 

 

cool cool cool

 Feb 27, 2018
 #2
avatar+594 
+1

thank you so much!

adore.nuk  Feb 27, 2018

11 Online Users

avatar