Answer:
Never
Never
Always
Always
Never
Step-by-step explanation:
Substitute (x) for another number, I used (1), I if works then the answer is always and if it doesn't the answer is never. If you are unsure of your answer you can double-check by substituting another number instead.
Substitute the x-value and see if you get the corresponding y-value. The corresponding y-value an x-value of 3 in this equation should be


Since the coordinate (3,32) does not represent that, it is a false solution
Answer:
the number you're looking for is 9.5
Step-by-step explanation:
4x-7 = 12+2x
2x-7 = 12
2x = 19
x = 9.5
108 miles 3 hours = 36 mph upstream
108 miles 2 hours = 54 mph downstream
bv = boat velocity in still water
cv = current velocity
bv -cv = 36
bv +cv = 54 Adding both equations
2*bv = 90
boat velocity in still water = 45 mph
since bv + cv = 54
then we know the current velocity = 9 mph