Solve for z. Show ALL work:
7z - 18 = -2z + 18
2006-10-26 04:31:37 · 10 answers · asked by cak 1 in Science & Mathematics ➔ Mathematics
Okay dear
■ 7z - 18 = -2z + 18
■ 7z + 2z = 18 + 18
■ z ( 7 + 2 ) = 36
■ 9z = 36
■ z = 36 / 9
■ z = + 4
Good Luck darling ♣
2006-10-26 08:56:53 · answer #1 · answered by sweetie 5 · 6⤊ 0⤋
7z - 18 = - 2z + 18
7z - 18 + 2z = - 2z + 18 + 2z
9x - 18 = 18
9z - 18 + 18 = 18 + 18
9z = 36
9z/9 = 36/9
z = 4
The answer is z = 4
Insert the z value into the equation
- - - - - - - - - - - - - - -
7z - 18 - = - 2z + 18
7(4) - 18 = - 2(4) + 18
28 - 18 = -8 + 18
10 = 10
- - - - - - - -s-
2006-10-26 05:09:45 · answer #2 · answered by SAMUEL D 7 · 0⤊ 0⤋
7z - 18 = -2z + 18
+2z +2z
9z - 18 = 18
+18 +18
9z=36
divide both sides by 9
z=4
2006-10-26 04:34:16 · answer #3 · answered by JitterBug589 3 · 0⤊ 0⤋
In the third equation, y and z are both unit variables, so write that equation in terms of the others. -2x - y - z = -18 ---> 2x + y + z = 18 y = 18 - 2x - z Now plug that into the other two equations. 2x + 3 * (18 - 2x - z) - 2z = 3 2x + 54 - 6x - 3z - 2z = 3 -4x - 5z = -51 4x + 5z = 51 -5x - 4y - 2z = -46 5x + 4y + 2z = 46 5x + 4(18 - 2x - z) + 2z = 46 5x + 72 - 8x - 4z + 2z = 46 -3x - 2z = -26 3x + 2z = 26 4x + 5z = 51 ---> 12x + 15z = 153 3x + 2z = 26 ---> 12x + 8z = 104 7z = 49 z = 7 3x + 2 * 7 = 26 3x + 14 = 26 3x = 12 x = 4 y = 18 - 2x - z y = 18 - 2 * 4 - 7 y = 18 - 8 - 7 y = 3
2016-05-21 22:16:31 · answer #4 · answered by Anonymous · 0⤊ 0⤋
7z - 18 = -2z + 18
7z + 2z = 18 + 18
9z = 36
z = 36/9
z = 4
2006-10-26 04:40:27 · answer #5 · answered by crazyprecious 2 · 0⤊ 0⤋
7z - 18 = -2z + 18
7z = -2z + 18 +18
7z = -2z + 36
7z + 2z= 36
9z = 36
z = 36/9
z = 4
2006-10-26 04:35:39 · answer #6 · answered by Anonymous · 0⤊ 0⤋
7z - 18 = -2z + 18
add 2z to both sides:
9z-18=18
add 18 to both sides:
9z=36
now all you have to do is divide by 9 to get the answer:
z=4
Hope that helps!
2006-10-26 04:32:57 · answer #7 · answered by D 3 · 0⤊ 0⤋
7z-18 = -2z + 18( add 2z on both sides)
9z - 18 = 18 ( add 18 on both sides)
9z = 36 (divide both sides by 9)
z = 4
2006-10-26 04:33:52 · answer #8 · answered by yanesh_r 1 · 0⤊ 0⤋
z=4
(7z - 18 = -2z + 18
7z+2z=18+18
z(7+2)=36
z*9=36
z=36/9
z=9*4/9
z=4.)
2006-10-26 04:41:19 · answer #9 · answered by Anonymous · 0⤊ 0⤋
9z=36
z=4
DO YOUR OWN HOMEWORK-THIS ONE WAS WAY TO EASY TO WASTE A Q.
2006-10-26 04:33:34 · answer #10 · answered by Sharp Marble 6 · 0⤊ 0⤋