A spread of +7.5 means that the team must either win the game or lose by 7 or less points/goals/runs for the spread bet to win. A spread bet is a bet on the margin of victory with a handicap (or line) attached to it, in this case the handicap is +7.5.

If the Bulls lose the game or win by fewer than seven points, they fail to cover the spread (meaning Clippers bettors cash their wager). What if Chicago wins by exactly seven points? It's called a push,  and all bets are refunded (no winner, no loser).