Question

current skill
if z = 12, which equation is true?
36z + 10 = 7
6.5z + 8.5 = 86.5
\frac{6}{z}+ 6 = 8
6z - 6 = -8

Explanation:

Step1: Check first equation ($36z + 10 = 7$)

Substitute \( z = 12 \): \( 36\times12 + 10 = 432 + 10 = 442
eq 7 \).

Step2: Check second equation ($6.5z + 8.5 = 86.5$)

Substitute \( z = 12 \): \( 6.5\times12 + 8.5 = 78 + 8.5 = 86.5 \). This matches.

Step3: Check third equation ($\frac{6}{z}+6 = 8$)

Substitute \( z = 12 \): \( \frac{6}{12}+6 = 0.5 + 6 = 6.5
eq 8 \).

Step4: Check fourth equation ($6z - 6 = -8$)

Substitute \( z = 12 \): \( 6\times12 - 6 = 72 - 6 = 66
eq -8 \).

Answer:

\( 6.5z + 8.5 = 86.5 \) (the second equation from the left)