Answer:
Two times at (-1,0) and (2.5,0)
Step-by-step explanation:
When the graph intersects or touches x-axis, y is equal to 0
so y = -2x^2 + 3x + 5
=> 0 = -2x^2 + 3x + 5
The formula to solve a quadratic equation of the form ax^2 + bx + c = 0 is equal to x = [-b +/-√(b^2 - 4ac)]/2a
so a = -2
b = 3
c = 5
substitute in the formula
x = [-3 +/- √(3^2 - 4x-2x5)]/2(-2)
x = [-3 +/- √(9 + 40)]/(-4)
x = [-3 +/- 7]/(-4)
x1 = (-3 + 7)/(-4) = 4/-4 = -1
x2 = (-3 - 7)/(-4) = -10/-4 = 5/2 = 2.5
so the graph has two x-intercepts (-1,0) and (2.5,0), therefore it intersects x-axis two times
Answer:
68 %
Step-by-step explanation:
The Empirical rule formula states that:
• 68% of data falls within 1 standard deviation from the mean - that means between μ - σ and μ + σ.
• 95% of data falls within 2 standard deviations from the mean - between μ – 2σ and μ + 2σ.
• 99.7% of data falls within 3 standard deviations from the mean - between μ - 3σ and μ + 3σ.
Mean of 96 and a Standard deviation of 17
Applying , the first empirical rule for 1 standard deviation from the mean, we have:
μ - σ
96 - 17
= 79
μ + σ
96 + 17
= 113
Therefore, the percentage of IQ scores that are between 79 and 113 is 68%
Answer:
Step-by-step explanation:
Answer:
1h 18min
Step-by-step explanation:
Not sure if that is what the problem is asking you.
Answer:
0 = 
Step-by-step explanation:
0= 0.52359877
