Aprojectile is fired directly upward. the compound inequality 89 – 9.8t < 10.6 or 89 – 9.8t > 20.4 represents a projectile’s velocity that is less than 10.6 m/s or greater than 20.4 m/s. solve the compound inequality. the solution to the inequality 89 – 9.8t < 10.6 is ? . the solution to the inequality 89 – 9.8t > 20.4 is? . to determine when the projectile hits the ground, solve 89 – 9.8t = 0 for t. rounding to the nearest whole second, t is about ? seconds. the viable solution set is ?

Given compound inequality 89 – 9.8t < 10.6 or 89 – 9.8t > 20.4.

Let us solve them one by one.

89 – 9.8t < 10.6

Subtracting 89 from both sides, we get

89-89 – 9.8t < 10.6 - 89

-9.8t < -78.4

Dividing both sides by -9.8, we get

t > 8.

Note: Inequality sign get flip on dividing both side by a negative number.

89 – 9.8t > 20.4

Subtracting 89 from both sides, we get

89-89 – 9.8t < 20.4 - 89

-9.8 t < - 68.6.

Dividing both sides by -9.8, we get

t < 7

Note: Inequality sign get flip on dividing both side by a negative number.

The solution to the inequality 89 – 9.8t < 10.6 is t > 8. The solution to the inequality 89 – 9.8t > 20.4 is t < 7.

When the projectile hits the ground:

89 – 9.8t = 0

Subtracting 89 from both sides, we get

89 - 89 – 9.8t = 0 -89.

-9.8t = -89.

Dividing both sides by 9.8, we get

to the nearest whole second  t is about 9 seconds.Therefore, variable solution set is {t < 7, t > 8, t = 9}.

We need more info then that

The answer is option c.