*In the other example, of Y = - 1/2 x ***4** - 4. If the x means times, then how can anyone know if when you write an x if you mean the variable x or a symbol for multiplication?

Y = (-1/2)x - 4. So x = 4

Clearly you just can't ignore the 2 in the denominator.

So you need to compute (-1/2)(4) - 4

Let's look at (-1/2)(4) first. There are to steps. One is to get the sign and another is to get the number. The sign of (-1/2) is negative and the sign of 4 is positive. So the final sign is negative (since -*- = +). Now onto finding the number, since we found the sign we can ignore the signs, (1/2)*4 can (and SHOULD) be read as half of four. Well 1/2 of 4 is 2. So we now know that (-1/2)*4 = -2

Let's finish up: (-1/2)(4) - 4 = -2 -4. You take away 2 and then take away 4 you took away 6. So (-1/2)(4) - 4 = -6.