solve for the letter z
2007-07-12 17:54:37 · 7 answers · asked by breezy_0602 1 in Science & Mathematics ➔ Mathematics
-1.3z - 9.4 = -0.4z + 8.6
-1.3z+0.4z=8.6+9.4
-0.9z=18
-z=18/0.9=20
z= -20
2007-07-12 18:00:36 · answer #1 · answered by Jain 4 · 0⤊ 0⤋
-1.3z - 9.4 = -0.4z + 8.6
- 1.3z + 0.4z = 8.6 + 9.4
- 0.9 z = 18.0
z = - 18/ 0.9
z = -180 / 9
z = - 20
or
10(-1.3z - 9.4) =10( -0.4z + 8.6)
- 13z - 94 = - 4z + 86
-13z + 4z = 86 + 94
- 9z = 180
z = - 180 / 9
z = -20
you can check the answer by substituting the value of z = - 20 in the equation
- 1.3 * - 20 - 9.4 = - 0.4 * 20 + 8.6
26 - 9.4 = 8 + 8.6
16.6 = 16.6
2007-07-13 03:14:46 · answer #2 · answered by Anonymous · 0⤊ 0⤋
Another way to approach the problem is to get rid of those darned decimals. Multiply the whole equation by 10.
10 [-1.3z - 9.4 = -.4z + 8.6]
-13z - 94 = -4z + 86
-13z + 4z = 94 + 86
-9z = 180
z = -20
2007-07-13 01:09:10 · answer #3 · answered by moni m 1 · 0⤊ 0⤋
-1.3z - 9.4 = -0.4z + 8.6
-1.3z = -0.4z + 18 (Add 9.4 to each side)
-.9z = 18 (Add 0.4z to each side)
z = -20 (18 divided by -.9)
2007-07-13 01:06:38 · answer #4 · answered by Kelli B 2 · 0⤊ 0⤋
add 9.4 to both sides. the 9.4 on the left zeroes out. on the right 8.6 + 9.4 is 18. the new equation is -1.3z=-.4z + 18.
then you add .4z to both sides. on the left it becomes -.9z. on the right the -.4z zeroes out. the new equation is -.9z=18.
divide -.9 from both sides, it becomes z=18/-.9
x= 20
2007-07-13 01:05:44 · answer #5 · answered by first timer 1 · 0⤊ 0⤋
-1.3z - 9.4 = -0.4z + 8.6
-1.3z+0.4z=8.6+9.4
-0.9 z = 18
z= - 20
2007-07-13 01:04:34 · answer #6 · answered by zohair 2 · 0⤊ 0⤋
- 1.3 z - 9.4 = - 0.4 z + 8.6
- 9.4 - 8.6 = - 0.4 z + 1.3 z
- 18 = 0.9 z
- 180 = 9 z
z = - 20
2007-07-16 06:26:03 · answer #7 · answered by Como 7 · 0⤊ 0⤋