A=pR^2-2pr^2, since R=15 and r=7.5
A=225p-112.5p
A=112.5p
A≈353.25 ft^2
Answer:
the last one 
Step-by-step explanation:
Answer:
7) 230mm
8) 98m
Step-by-step explanation:
7)
7x+8+6x+6+9x-4 =22x+10
if x is 10 mm, 22(10)+10 =230mm
8) perimeter of rec =2( l + w )
=2 ( 2x-5+2x+6 ) = 8x + 2
if x is 12 metres, 8(12)+2 =98m
Answer:
Step-by-step explanation:
KE = ½mv²
KE₁₀ = ½(1100)10² = 55000 = 55 kJ
KE₃₀ = ½(1100)30² = 495000 = 495 kJ
9 times greater
Answer:
y =
x - 11
Step-by-step explanation:
The equation of a line in slope- intercept form is
y = mx + c ( m is the slope and c the y- intercept )
Calculate m using the slope formula
m = 
with (x₁, y₁ ) = (2, - 4) and (x₂, y₂ ) = (6, 10)
m =
=
=
, thus
y =
x + c ← is the partial equation
To find c substitute either of the 2 points into the partial equation
Using (2, - 4) , then
- 4 = 7 + c ⇒ c = - 4 - 7 = - 11
y =
x - 11 ← equation of line