Question

How many solutions does the following equation have? 9z - 6 + 7z = 16z - 6

Answer 1

Hello there!

9z - 6 +7z = 16z - 6
16z - 6 = 16z - 6
Subtract 16z from both sides
16z - 6 - 16z = 16z - 6 - 16z
-6 = -6
Now, add 6 to both sides
-6 + 6 = -6 + 6
0 = 0
Thus,
All real numbers are solutions.

Answer 2

Hello Peredhel.
We have to solve for z...

The unknown term 'z' must be at left and the known terms at the right.

The first thing to do, is to move all the 'z' at the left of equal but changing sign. The known terms must go to the right of equal and changing sign.

So, rewrite as:

9z + 7z - 16z = -6 + 6

0z = 0

The equation is indeterminated. There are infinite solutions, all real numbers.

Hope that helped!