Multiply (1 - 7x)(1 + 9x)

To multiply the expressions (1 - 7x)(1 + 9x), we can use the FOIL method, which stands for First, Outer, Inner, Last.

First, multiply the First terms: 1 * 1 = 1
Outer, multiply the Outer terms: 1 * 9x = 9x
Inner, multiply the Inner terms: -7x * 1 = -7x
Last, multiply the Last terms: -7x * 9x = -63x²

Now, we can combine these terms:
(1 - 7x)(1 + 9x) = 1 + 9x - 7x - 63x²

Simplifying, we have:
1 + 2x - 63x²