Hello there!
Let's use foil.
First: 4x * 2x = 8x^2
Outside: 4x * -9 = -36x
Inside: -7 * 2x = -14x
Last: -7 * -9 = 63
Now, let's combine these.
8x^2 - 36x - 14x + 63
Finally, we can simplify this
8x - 50x + 63
I hope I helped!
Let me know if you need anything else!
~ Zoe