B=3/4a
a+b=21

A. a=30 b=15
B. a=371/4 b=-161/4
C. a=20 b=11
D. a=12 b=9

D option

Step-by-step explanation:

a + b = 21

Placing value of b as 3/4a,

a + 3/4a = 21

7a/4 = 21

a = 12

Putting value of a in b=3/4a,

b = 3 × 12/4 = 9

a = 12, b = 9

Hope it helps.

d 25 pi/6

step-by-step explanation:

the diameter is 10 inches

the radius is 1/2 of the diameter or 5 inches

the area of the circle is

a = pi r^2

  = pi 5^2

  = 25 pi

the slice is 60 degrees of the entire circle.

60 degrees out of 360   60/360 = 1/6

the area of the slice is 1/6 of the circle

a slice = 1/6 a circle

a slice = 1/6 * 25 pi

a. 32 degrees

step-by-step explanation:

here we have to use the rule.

m∠e = 1/2 (major arc - minor arc)

m∠e = 1/2 (212 - 148)

m∠e = 1/2 (64)

m∠e = 32 degrees

answer: a. 32 degrees

you