AK = 640
Δ ABC and ΔFJK are similar. They are small triangles.
ΔCDF is the big triangle.
640 / 2 = 320 m= CF
AC & FK= 320/2 = 160 m each
2AC = CF = 2FK
2(160) = 320 = 2(160)
BG = 20 m
20/160 = x / 320
20*320 = 160x
6400 = 160x
6400/160 = x
40 = x
Area of CDF = (40 m * 320 m)/2 = 12,800 / 2= 6,400 m²
The answer is 28 years
At = A0 * e^(-k * t)
At = 12 g
A0 = 15 g
k = 7.9 × 10^-3 = 0.0079
t = ?
12 = 15 * e^(-0.0079 * t)
12/15 = e^(-0.0079 * t)
0.8 = e^(-0.0079 * t)
Logarithm both sides (because ln(e) = 1:
ln(0.8) = ln(e^(-0.0079 * t))
ln(0.8) = (-0.0079 * t) * ln(e)
-0.223 = -0.0079 * t
t = -0.223 / -0.0079
t = 28.23
t ≈ 28 years
Answer:
7:17
Step-by-step explanation:
There are 7 girls and 10 boys taking gymnastics lessons. Write the ratio that compares the number of girls taking gymnastics lessons to the total number of students taking gymnastics lessons
Total number of students taking gymnastics classes = 7 girls + 10 boys = 17 students
Hence:
the ratio that compares the number of girls taking gymnastics lessons to the total number of students taking gymnastics lessons
= 7 : 17
Answer: b
Explanation: A and C are wrong because a negative times a positive is a negative
And D is wrong because a positive times a positive is a positive