Answer:
see explanation
Step-by-step explanation:
Given the 2 equations
y = x² + 2x + 7 → (1)
y - 7 = x → (2)
Rearrange (2) expressing y in terms of x by adding 7 to both sides
y = x + 7 → (3)
Substitute y = x + 7 into (1)
x + 7 = x² + 2x + 7 ( subtract x + 7 from both sides )
0 = x² + x ← factor out x from each term
0 = x(x + 1)
Equate each factor to zero and solve for x
x = 0
x + 1 = 0 ⇒ x = - 1
Substitute these values into (3) for corresponding values of y
x = 0 → y = 0 + 7 = 7
x = - 1 → y = - 1 + 7 = 6
The solutions are
(- 1, 6 ) and (0, 7 )
Last option - angle BAF and FAD
The enclosed shape is that of a trapezoid. The area of a trapezoid is the product of the height of it (measured perpendicular to the parallel bases) and the average length of the two parallel bases. The formula is generally written ...
... A = (1/2)(b₁ + b₂)·h
Here, the base lengths are the y-coordinates at x=4 and x=9. The height is the distance between those two x-coordinates: 9 - 4 = 5.
You are expected to find the y-values at those two points, then use the formula for the area of the trapezoid.
You can save a little work if you realize that the average of the two base lengths is the y-coordinate corresponding to the average x-coordinate: (9+4)/2 = 6.5. That is you only need to find the y-coordinate for x=6.5 and do the area math as though you had a rectangle of that height and width 5.
Going that route, we have
... y = 2(6.5) - 1 = 13 - 1 = 12
Then the trapezoid's area is
... A = 12·5 = 60 . . . . square units.
Correct question is;
A bag contains 10 counters. 6 of them are white. A counter is taken at random and not replaced. A second counter is taken out of the bag at random. Calculate the probability that only one of the two counters are white
Answer:
probability that only one of the two counters is white = 8/15
Step-by-step explanation:
To solve this question, first of all, let's look at probability we would have to either draw two white counters or two non-white counters (4/10 * 3/9).
Probability(draw 2 white counters) = (6/10 × 5/9) = 30/90 = 1/3
Probability(draw 2 non-white counters) = (4/10 × 3/9) = 2/15
Now, In all other cases, we'll draw exactly one white and one non-white counter, so the odds of this would be;
P(one white counter and one non-white counter) = 1 - [1/3 + 2/15)
= 1 - 7/15 = 8/15
