Answer:
the answer is in last picture
8(x+3)
total means addition and times means multiplication so when you put it together you get 8*x+3 and because you want the total of x*3 you put it in parentheses
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Answer: a capital letter
Explanation: The most basic figure in geometry is called a point.
For example, ·A or ·Q.
Notice that above, points are usually labeled with a capital letter.
Answer:
Sister = 15 years old
Brother = 12 years old
Step-by-step explanation:
Right now, if the brother is B years old and the sister is S years old, B = (4/5)S because the ratio from brother to sister is 4:5, so if one unit is X, B = 4X and S = 5X
Three years ago, the brother was B-3 years old and the sister was S-3 years old. Keeping one unit as X, we have
B = 3X
S = 4X
B-3 = (3/4)(S-3)
Therefore, we have a system of equations
B = (4/5)S
B-3 = (3/4)(S-3)
Substitute (4/5)S for B into the second equation to only have one variable
(4/5)S - 3 = (3/4)(S-3)
(4/5)S - 3 = (3/4)S - 9/4
add 3 to both sides and subtract (3/4)S from both sides to isolate the variable and its coefficient
(1/20)S = 3/4
multiply both sides by 20 to isolate the S
S = 15
B = (4/5)S = 12
Answer:
a) 21m - 0.87 = m
b) m = 0.0435 mg
21(0.0435) - 0.87 = 0.0435
0.9135 - 0.87 = 0.0435
0.0435 = 0.0435
True statement, so correct
c) 21m - 0.87 = m
20m = 0.87
m = 0.87/20
m = 0.0435 mg