The opposite of -48 is positive 48, Written as just 48.
Answer:

Step-by-step explanation:
STEP 1: Subtract 11x from 7x.
STEP 2: Subtract 10 from 12.
Answer: 80 feet
Step-by-step explanation:
We can write these as fractions and do cross multiplication with the numerator being the height of the object while the denominator being the length of the shadow:
5 * 128 = 8x
640 = 8x
80 = x
Thus, the height of the lighthouse is 80 feet tall.
Here, f(x) = kx
k = f(x)/x
k = 48/8
k = 6
So, when x = 2,
f(x) = 6 * 2
z = 12
In short, Your Answer would be: 12
Hope this helps!