Answer:
−2.5d−0.7
Step-by-step explanation:
1 Expand by distributing terms.
-(2.5d+5)+4.3
2 Remove parentheses.
-2.5d-5+4.3
3 Collect like terms.
-2.5d+(-5+4.3)
4 Simplify.
-2.5d-0.7
Answer: There is a difference between rote counting and rational counting. Rote counting involves the memorization of numbers. Rational counting tells children "how many there are." For children to count rationally, they need to demonstrate one-to-one correspondence.
So solve for the equations of the lines
y=mx+b
m=slope
b=y intercept
line 1=
(-4,5)
(0,2)
(x,y)
slope=(y1-y2)/(x1-x2)
x1=-4
y1=5
x2=0
y2=2
subsitute
(5-2)/(-4-0)=3/-4=-3/4
slope=-3/4
subsitute
y=-3/4x+b
subsitute one of the points
(0,2)
x=0 and y=2 is one solution
2=-3/4(0)+b
2=0+b
2=b
the equation is y=-3/4x+2
other line
(0,5)
(4,2)
x1=0
y1=5
x2=4
y2=2
sybsitute
(5-2)/(0-4)=3/-4=-3/4
slope=-3/4
subsitute
y=-3/4x+b
now subsitute one of the points to solve for b
(0,5)
x=0 and y=5 is one solution
5=-3/4(0)+b
5=0+b
5=b
y=-3/4x+5
so we have the lines/equations
y=-3/4x+2 and y=-3/4x+5
(at this point we can see that since slopes are the same and the y intercepts are different, they are paralell and therefor have 0 solutions, but for those who don't know paralellline thingie read on)
solve for common (x,y)
y=-3/4x+2
y=-3/4x+5
subsitute
-3/4x+2=y=-3/4x+5
-3/4x+2=-3/4x+5
subtract 2 from both sides
-3/4x=-3/4x+5
add 3/4x to both sides
0=5
fasle
there are no solutions
the answer is A: 0 solutions
Principle: divide the correct possibilities by the total nr. of possibilities to find the probability.
6. P(green) = 5 / (7+5+6) = 5/18
7. P(red) = 6 / 18 = 1/3
8. P(not green) = P(red | blue) = (6+7)/18 = 13/18
9. P(HH) = 5/25 = 1/5
10. P(HT) = 16/25
11. P(NOT TT) = P(HH | HT) = (5+16)/25 = 21/25
12. P(HH | TT) = (5+4)/25 = 9/25
13. P(5) = 1/6. P(H) = 1/2. P(5 & H) = 1/6*1/2 = 1/12. If you draw all the possibilities, you'll find there are 12. One of them is 5 & Heads.
