The answer is 11/36
2/12 chance of rolling fours
because there are 2 sides containing a four on both dice combined and 12 sides in total.
Doubles mean you have to roll the same number simultaneously so let’s say we want to calculate the probability for double ones: then it’s 1/6 on the first dice for a one, and 1/6 on the second dice to land on a one as well.
I personally like to imagine a box like this:
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If you have one dice then it’s just a random segment on one of the lines. If you want the specific result from two dice then you want two specific segments which is also the 1 specific tile out of 36 (6 width times 6 height). So you multiply.
1/6 * 1/6 = 1/36 chance to roll double of ones
And 1/36 chance to roll double twos, threes, fours, fives, and sixes. But we don’t count the double fours because any four will do. So:
1/36 * 5 = 5/36
So for the probability of either doubles or containing a four is the probability of doubles of either number plus the probability of either dice being a four:
5/36 + 2/12 =
5/36 + 6/36 =
11/36
Supplementary adjacent angles form a "linear pair." Together, they make a line. The angle supplementary to 85° will be slightly obtuse, just as 85° is slightly acute.
Answer:
x < -5
Step-by-step explanation:
Distribute 4 to x and 10: 4x + 40 < 20
Subtract 40 from both sides: 4x < -20
Divide by 4: x < -5
Part 1: The general form for this matches y^2 = -4cx, which implies that this opens to the left. (Imagine assigning any value of y, whether positive or negative, which would result in a positive left-hand value. Then to match this sign, the value of x must be negative so that the right-hand side becomes positive as well.)
Part 2: The distance from the vertex to the directrix is given by c. This equation has its vertex at the origin (0, 0). If it opens to the left, the directrix is a vertical line to the right of the origin. This equation is y^2 = -4(1/2)x, so c = 1/2, and the directrix has the equation x = 1/2.
Part 3: The focus is inside the parabola, but it is the same distance from the vertex as the directrix. This distance is 1/2 units, and it will be to the left of the vertex. So the focus is at (-1/2, 0).
