Let the points be P (-85,-10) and Q (12,-2)
Distance PQ = 97.3
Refer image
Answer:
P = 0.14t +2.25
Step-by-step explanation:
The statement that "the price of a school lunch ... has risen at a constant rate" is telling you that the price can be modeled by a linear equation. If P is the price, and t is years after 2012, you are given two points on the line:
(t, P) = (0, 2.25) and (7, 3.20)
You can use these points to find the equation of the line in the usual way.
m = (y2 -y1)/(x2 -x1) . . . . . . slope of a line through (x1, y1) and (x2, y2)
m = (3.20 -2.25)/(7 -0) = 0.95/7 ≈ 0.14
The first point tells you the equation intercept, so the relationship between P and t is ...
y = mx +b . . . . . . . m = slope; b = y-intercept. We're using (t, P) for (x, y).
P = 0.14t +2.25
Answer:
4. z = -1
5. x = 3.5 or 7/2
Step-by-step explanation:
4.
-4z + 8 = 7z +14 + 5
-4z + 8 = 7z + 19
8 = 11z + 19
-11 = 11z
-1 = z
5.
6-x/5 = 6-3x+6/3
6-x/5 = 12-3x/3
18 - 3x = 60-15x
-3x = 42 - 15x
12x = 42
x = 3.5 or 7/2
A)
75% she knows for sure
Out of the remaining 25%, she has a 1/5 or 20% chance of getting it right. So,
1/4 x 1/5 x 100 = 5%
Total chance of getting a question right:
75 + 5 = 80%
b) If the total is 40, she can expect to get
80% x 40 = 32 questions correct.