2x^2 - 11 = 87
2x^2 = 87 + 11 = 98
x^2 = 98/2 = 49
x = sqrt (49) = + or - 7
The inequality is t < 55
<em><u>Solution</u></em><em><u>:</u></em>
Given that, To qualify for the championship a runner must complete the race in less than 55 minutes
Let "t" represent the time in minutes of a runner who qualifies for the championship
Here it is given that the value of t is less than 55 minutes
Therefore, "t" must be less than 55, so that the runner qualifies the championship
<em><u>This is represented by inequality:</u></em>

The above inequality means, that time taken to complete the race must be less than 55 for a runner to qualify
Hence the required inequality is t < 55
Answer:
Γ = 15
Step-by-step explanation:
Given
f(x) = x² - 8x + Γ
with a = 1, b = - 8 and c = Γ , then
sum of zeros α + β = -
= -
= 8
product of zeros = αβ =
= Γ
Given α - β = 2 , then
(α - β)² = 2²
α² - 2αβ + β² = 4 → (1)
and
(α + β)² = 8²
α² + 2αβ + β² = 64 → (2)
Add (1) and (2) term by term
2α² + 2β² = 68 ( divide through by 2 )
α² +β² = 34
Substitute α² + β² = 34 into (1)
34 - 2αβ = 4 ( subtract 34 from both sides )
- 2αβ = - 30 ( divide both sides by - 2 )
αβ = 15
Now
αβ = Γ = 15
Thus
f(x) = x² - 8x + 15
<u><em>Answer:</em></u>
The bird is approximately 9 ft high up in the tree
<u><em>Explanation:</em></u>
The required diagram is shown in the attached image
Note that the tree, the cat and the ground form a right-angled triangle
<u>Therefore, we can apply special trigonometric functions</u>
<u>These functions are as follows:</u>

<u>Now, taking a look at our diagram, we can note the following:</u>
α = 25°
The opposite side is the required height (x)
The adjacent side is the distance between the cat and the tree = 20 ft
Therefore, we can use the <u>tan function</u>
<u>This is done as follows:</u>
which is 9 ft approximated to the nearest ft
Hope this helps :)
Answer:
c
Step-by-step explanation: