How to write an equivalent expression for n time a using o
        
             
        
        
        
Answer:
2x + y = 5
y = 4x – 1
Substitute (2, 1) into system, then:
2x + y = 5  => 2 x 2 + 1 = 5 => 5 = 5 (satisfied)
y = 4x– 1   => 4 x 2 - 1 = 1  => -7 = 1 (not satisfied)
=> Option 3 is correct.
Hope this helps!
:)
 
        
             
        
        
        
Let L be the length 
Let w be the width 
Let p be the perimeter 
L+w+L+w=p
L=w+20
3L+2w+3L+2w=240
Sub the first equation in for L in the second equation and solve for w
3(w+20)+2w+3(w+20)+2w=240
3w+60+2w+3w+60+2w=240
10w+120=240
10w=240-120
10w=120
W=120/10
W=12
Sub w into the first equation and solve for L
L=w+20
L=12+20
L=32
Hope this helps!
        
             
        
        
        
Answer:
x = 3, y = 4 and z = -5.
Step-by-step explanation:
Use the elimination method:
-3x + 2y + z = -6...........(1)
x + 3y + 2z = 5..............(2)
4x + 4y + 3z = 13..........(3)
Multiply the first equation by -2:
6x - 4y - 2z = 12   Add this to equation (2):
7x  - y  = 17...........(4)
Now Multiply equation (2) by 3 and equation (3) by -2
3x + 9y + 6z = 15 ............(5)
-8x - 8y - 6z = -26............(6)   Adding (5) + (6):
-5x + y = -11..........(7)
Now Add (7) and (4):
2x = 6
x = 3.
Now  substitute for x in (4):
7(3) - y = 17
-y = 17 - 21 = -4
y = 4.
Finally substitute for x and y in equation (3) to find z:
4(3) + 4(4)  +3z = 13
3z = 13 - 12 - 16 = -15
z = -5.
 
        
             
        
        
        
Answer:
95
Step-by-step explanation:
For example, let's say with have the equation 
x
+
5
When 
x
=
1
, then 
x
+
5
=
6
When 
x
=
2
 then 
x
+
5
=
7
Hope that was helpful.