Solution (1) using angles of sectors:
Area of A = pi r^2 x 90/360 = 4.9
Area of B = pi r^2 x 270/360 = 14.2
Check: Area of A/B = 4.9/14.72 = 1/3 (as given)
Solution (2) using given info:
Area of B + Area of A = area of circle
Area of B + 1/3 Area of B = 3.14 * (2.5)^2 = 19.625
4/3 Area of B = 19.625
Area of B = 3/4 * 19.625
Area of B = 14.72
Area of A = 1/3 * 14.72 = 4.9
There is more solutions to this problem , like polar coordinate integration , and so on. for more just request.
6. One variable only so pretty straightforward.
length-x+4
width-x
x+x+4=80
2x=76
x=38
x+4=42
answer: length 42cm and width 38cm
7. Another money problem!
n-# of nickels
q-# of quarters
n=3+q
0.05n+0.25q=2.85
Substitution works like a charm!
0.05(3+q)+0.25q=2.85
0.15+0.05q+0.25q=2.85
0.3q=2.7
q=9
n=3+q
n=3+9
n=12
answer: 9 nickels and 12 quarters
8. One variable situation again.
Ann's money-2b+9
Betty's money-b
b+2b+9=60
3b=51
b=17
2b+9=43
answer: Ann has $43 and Betty has $17.
9. # of red m&m's-x+1
# of blue m&m's-x
x+1+x=13
x=6
x+1=7
answer: 6 blue and 7 red m&m's
10. a-number of adult tickets
s-number of student tickets
a+s=785 ----> a=785-s
5a+2s=3280
5(785-s)+2s=3280
-3s=-645
s=215
a+s=785
a+215=785
a=570
answer: 215 children tickets and 570 adult tickets
D is the answer
(4+8)+1 = 13
4+(8+1) = 13
Therefore equation D is true
Ill try to answer your question
2x+4y+0.50z=36 represents the situation.
Step-by-step explanation:
Let,
Drinks = x
Sandwich = y
And,
Chips = z
Total amount on these items = $36
According to the statement;

2x+4y+0.50z=36 represents the situation.
Keywords: Linear equations
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