Answer:
a = 30
b = 40
C
Step-by-step explanation:
This requires that you use a proportion.
a / (a + 15) = 40 / 60
The small triangle's sides are in proportion to the large triangles sides.
Reduce the right. Divide top and bottom by 20
a/(a + 15) = 40/20 // 60/20
a/(a + 15) = 2/3
Cross multiply
3a = 2(a + 15) Remove the brackets on the right.
3a = 2a + 30
Subtract 2a from both sides
3a-2a = 30
a = 30
Find B
b is done exactly the same way.
b/(b+20) = 2/3
3b = 2b + 40
3b - 2b = 40
b = 40
Answer:
2km/m
Step-by-step explanation:
6 laps = 10km
(because 3 x 2 = 6 and double 5km as well)
Distance divide time = speed
20 mins divided by 10km = 2km per minute
Answer:
a = 3
b = 2
c = 0
d = -4
Step-by-step explanation:
Form 4 equations and solve simultaneously
28 = a(2)³ + b(2)² + c(2) + d
28 = 8a + 4b + 2c + d (1)
-5 = -a + b - c + d (2)
220 = 64a + 16b + 4c + d (3)
-20 = -8a + 4b - 2c + d (4)
(1) + (4)
28 = 8a + 4b + 2c + d
-20 = -8a + 4b - 2c + d
8 = 8b + 2d
d = 4 - 4b
Equation (2)
c = -a + b + d + 5
c = -a + b + 4 - 4b+ 5
c = -a - 3b + 9
28 = 8a + 4b + 2c + d (1)
28 = 8a + 4b + 2(-a - 3b + 9) + 4 - 4b
28 = 6a - 6b + 22
6a - 6b = 6
a - b = 1
a = b + 1
220 = 64a + 16b + 4c + d (3)
220 = 64(b + 1) + 16b + 4(-b - 1 - 3b + 9) + 4 - 4b
220 = 60b + 100
60b = 120
b = 2
a = 2 + 1
a = 3
c = -3 - 3(2) + 9
c = 0
d = 4 - 4(2)
d = -4
Answer:
two
Step-by-step explanation:
A ratio compares the relative sizes of two quantities .
The answer is B because the inverse of a squared number is the square root.