A. X ~ N(66, 6.25)
b.
Using a standard normal probability table to find probability values for the z-scores, we get:
P(65 < X < 69) = 0.1554 + 0.3849 = 0.5403
c. z= 0.524 and -0.524
1.31 = X - 66
X = 67.31
When z = -0.524, X = 64.69.
P(64.69 < X < 67.31) = 0.4
- × 9x = -9x
- × +8 = -8
-9x - 2x = -11x
-8 - -10 = +2
answer = -11x +2
Answer:
Step-by-step explanation:
From the upper isosceles triangle,
The answer is: x=±√5y [Note: If and only if at the lower triangle is NOT isosceles]
Exterior angle to the isosceles triangle = 2(2x^2 – 2x) [because the exterior angle of a triangle is equal to the sum of two opposite interior angles]
Therefore, the exterior angle = 4x^2 – 4x
Also,
The exterior angle is equal to the sum of the two interior base angles of the lower triangle
Thus, 4x^2 – 4x=(3x^2+4x) + (5y – 8x)
By collecting like terms,
4x^2 – 3x^2 – 4x – 4x + 8x – 5y = 0
x^2 – 5y = 0
x^2 = 5y
By taking the square root of both sides
x=±√5y
Learn more about triangles at brainly.com/brainly.com/question/29069807
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That is correct because he only has 50$ and all three books cost 60$ so he doesn't have enough hope i helped
