1.53
2.115
3.122
4.106
5.49
6.110
left to right
First add both number with x and then add both number with y and then add both numbers which is the answer to both equations and that is called linear combination.
At the time the cannonball reaches the ground, the vertical height of the cannonball from the ground is 0, i.e. h = 0.
Thus, the time it will take the cannonball to reach the ground is given by

Therefore, it will take the cannonball 8 seconds to reach the ground.
Answer:
Ana made a mistake from line 2 to 3
Step-by-step explanation:
From line 2 to 3, on the left side, ana <u>added</u> 2 and 3 but completely ignored the - in front of the 3. the correct answer would have been<u> -x - 21 = 3x + 19</u>