What is the area of a circle with a diameter of 8 cm, in square centimeters?

50.27 cm squared

Step-by-step explanation:

the diameter is across the whole circle, so divide 8 by 2 to find the radius. then use the formula A = πr^2 to find that answer.

you could shorten that by multiplying the diameter times pi.

-4

step-by-step explanation:

(-4+8)=-(4-8)=-8+4=-4

b

step-by-step explanation:

the equation of a line in point- slope form is

y - b = m(x - a)

where m is the slope and (a, b) a point on the line

calculate m using the slope formula

m = (y₂ - y₁ ) / (x₂ - x₁ )

with (x₁, y₁ ) = (0, 4) and (x₂, y₂ ) = (3, - 5) ← 2 points on the line

m = = = - 3

with m = - 3 and (a, b) = (3, - 5), then

y - (- 5) = - 3(x - 3), that is

y + 5 = - 3(x - 3) → b