9514 1404 393
Answer:
a) x = -1, x = 4
b) y = x^2 -3x -4
Step-by-step explanation:
a) We observe the x-intercepts are x = -1 and x = 4. These are the solutions to y = 0, which is usually what we want in cases like this.
The solutions are x=-1 and x=4.
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b) We know two of the factors are (x +1) and (x -4). There may be an additional constant factor for vertical scaling. One point we can check is the y-intercept.
y = a(x +1)(x -4)
For x=0, this is ...
y = a(1)(-4) = -4a
The y-intercept is y = -4, so we have a=1.
The factored equation is ...
y = (x +1)(x -4)
Multiplying this out gives the equation in standard form:
y = x^2 -3x -4
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<em>Additional comment</em>
Your teacher may want the standard form equation to be ...
x^2 -3x -4 = 0
This is the equation of two specific points: x=-1 and x=4. It is not the equation of the graph.
Answer:
middle left
Step-by-step explanation:
Answer: a) 1082, b) wider.
Step-by-step explanation:
Since we have given that
Margin of error = 0.1 millimeter = E
Standard deviation = 2 mm = σ
Critical value would be

a) Sample size would be

b) Sample size, n = 100
So, the margin of error would be

Since the margin of error in b part is more than a part, as we know that the higher the margin of error, the wider the confidence interval.
So, it would have wider confidence interval.
Hence, a) 1082, b) wider.
Answer:
- 40
Step-by-step explanation:
When a = 4, and x = -4:
Evaluating algebraic expressions simply involve substituting the given values for <em>a</em> and<em> x</em> into the expression, -9a + x.
Hence, -9a + x = -9(4) + (-4) = -36 - 4 = -40
Therefore, the correct answer is -40.