Answer:
<h2>x = -3</h2>
Step-by-step explanation:
<u>15 - 7x </u>= 9
4
-7x = 9(4) - 15
x = 21/-7
x = -3
proof:
<u>15 - 7(-3) </u>= 9
4
390
85(4)=50=390
....................
A product of two (or more) factor can be zero if and only if at least one of the factors is zero.
In other words, you cannot multiply two non-zero real numbers, and have zero as a result.
So, if we want the product of these two factors to be zero, at least one of them has to be zero.
The first factor is zero if

The second factor is zero if

The real solutions are {

}.
The imaginary solutions are {

}.
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