1: one solution
Explanation: We see that the variable x is equal to 9 (and only 9). Therefore there is only one solution
2: infinitely many solutions
Explanation: When an equation has infinitely many solutions, it means that any real number (aka all real numbers) would satisfy that equation. For example 2x = 2x. Any number you plug in for x would result in both sides being equal. So you know an equation has infinitely many solutions if both sides are the same
3: no solution
Explanation: 7 does not equal 4 so you can't solve this equation.
4: no solution
Explanation: 7 is not less than 7, that is impossible, so there is no solution.
5: one solution
Explanation: 8 is greater than or equal to -2, so this inequality is true, meaning it represents one solution
