She had a 88% chance because she used enough urn
We have to use a z-score percentile table for the standard normal distribution. It shows:
The 20th percentile = - 0.84
The 40th percentile = - 0.25
The 60th percentile = 0.25
The 80th percentile = 0.84
$200 x 12 = 2,400 (number of pencils they bought in 2006)
3/4 x 2,400 = 1,800 (number of pencils they used)
2,400 - 1,800 = 600 (number of pencils remaining)
1,800 - 600 = 1,200 (number of pencils needed)
They had to buy 1,200 more pencils in 2007.
They want you to combine the variables. So
−12x4 + 7x3 + 6x4 − 2x3 =
<span>5x3 − 6x4
</span>So you combine the coefficients, not the variable number, for instance -12+6=-6, and then you simply put the variable in the same place it was. You don't do anything else with it except what I just showed you : )
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y = x^2 -5x-6 is a quadratic equation.
On a graph, rather than a straight line, this type of equation forms what is known as a parabola, which means it goes one direction and then makes almost like a U-turn.
The point in which the parabola (as mentioned before) changes direction is called the vertex.
Specifically, y = x^2 -5x-6 has exactly 2 solutions. This means that there are 2 different possible answers to this equation.
The solutions, or roots, to this equation are x= 6 and x= -1.
If you look at the graph for this equation, the parabola opens upwards like a U, and the vertex is ( 5/2, -49/4).