B) 7 would make it true, since both 42/54 and 7/9= 0.77 repeating
To compare their speed (rate), we need to have the same time or same distance to use as a reference.
Matt ran 50 meters per 10 seconds. Molly ran 30 meters per 5 seconds. If she ran for 5 more seconds, she would have gone 30 more meters, for 30 meters per 10 seconds. Thus, Molly went faster.
Alternately, you could calculate their speeds in meters per (one) second and compare. 50 meters per 10 seconds is 5 meters per second, and 30 meters per 5 seconds is 6 meters per second.
-(z + (-17)) = 12 + 17
-(z - 17) = 12 + 17
Distribute -1:
-z + 17 = 12 + 17
Subtract 17 to both sides:
-z = 12
Multiply -1 to both sides:
z = -12
The slope, if increased, would make the line y=2x-7 steeper. If you were to increase the y intercept, you would just move the line, not tilt it. Suggest changing it to 4x-7 = y or 8x-7= y, if you increase the slope, it'll make it steeper.
