The "product" of two numbers means you multiply them.
So, you are multiplying (8-n), where n = "a number," by 7.
Then, when you decrease (subtract) this product by 5, you get 40.
So the whole thing looks like
7(8-n) - 5 = 40.
<span>The answer is that x = 21/9.
Start with the original: 4(2x - 1) - 7 = 4 - x + 6
Now distribute the 4:</span> <span> 8x - 4 - 7 = 4 - x + 6.
Now combine the like terms. 8x - 11 = -x + 10.
Now add x to both sides. 9x - 11 = 10.
Now add 11 to both sides. 9x = 21.
And divide by 9 on both side. x = 21/9. </span>
Part A: $225y+5x=$480
Part B: f(480)=225=5x
Part C: I'm not sure how to do this but I hope that A and B helps!