Answer:
A) x = − 1, y = 2, z = 3
Step-by-step explanation:
4x − 2y + 3z = 1
x + 3y − 4z = −7
3x + y +2z = 5
Lets eliminate x by multiplying the second equation by -4
4x − 2y + 3z = 1
-4x - 12y + 16z = 28
-----------------------------
-14y +19z = 29
Lets eliminate x by multiplying the second equation by -3
-3x + -9y +12z = 21
3x + y +2z = 5
---------------------------
-8y +14z =26
We now have 2 equations and 2 unknowns
-14y +19z = 29
-8y +14z = 26 Divide this by 2 = -4y +7z = 13
Multiplying the first equation by 4 and the second by -14
-56y +76z =116
56y -98z = -182
----------------------------
-22z =-66
Divide each side by -22
-22z/-22 = -66/-22
z=3
Now we need to find y
-14y +19z = 29
-14y +19(3) =29
-14y+ 57 = 29
-14y =29-57
-14y =-28
y =2
Now we need to find x
x + 3y − 4z = −7
x + 3(2) -4(3) =-7
x+6 -12 =-7
x-6 = -7
x = -1
Given A = {1, 3, 5, 7, 9} and B = {0, 1, 2, 3, 4, 5), find the intersect<br>
AB=
DanielleElmas [232]
An intersection is the numbers that are in both sets:
Intersect of AB is {1,3,5}
34.90+(.15)(1449-436)=186.85
Matt paid $70 for mp3 player.
Step-by-step explanation:
Given,
Cost of mp3 player = $149.99
Discount = 20%
Amount of discount = 20% of 149.99
Amount of discount = 
Amount of discount = 0.2*149.99
Amount of discount = $29.99
Sale price = Cost of mp3 - Amount of discount
Sale price = 
Rebate = $50
Amount paid by Matt = sale price - rebate
Amount paid by Matt = 120-50 =$70
Matt paid $70 for mp3 player.
Keywords: subtraction, percentage
Learn more about subtraction at:
#LearnwithBrainly
Step-by-step explanation:
Work: (A)
a) 20−4x=12−x+8−3x
20−4x=12−x+8−3x
20+−4x=12+−x+8+−3x
−4x+20=(−x+−3x)+(12+8)
−4x+20=−4x+20
−4x+20=−4x+20
−4x+20+4x=−4x+20+4x
20=20
20−20=20−20
0=0
In this equation... All real #s are solutions.
Work: (B)
b) 5x+4x−3=24+8x
5x+4x−3=24+8x
5x+4x+−3=24+8x
(5x+4x)+(−3)=8x+24
9x+−3=8x+24
9x−3=8x+24
9x−3−8x=8x+24−8x
x−3=24
x−3+3=24+3
x=27
Work: (C)
c) 5x+6=2x+6+3x−15
5x+6=2x+6+3x−15
5x+6=2x+6+3x+−15
5x+6=(2x+3x)+(6+−15)
5x+6=5x+−9
5x+6=5x−9
5x+6−5x=5x−9−5x
6=−9
6−6=−9−6
0=−15
HOPE THIS HELPS <3 :D
