The area of a circle is A = πr^2. We let A1 And A2 the areas of the circles and r1 and r2 the radius of each, respectivley.
A1 + A2 = 80π
Substitute the formula for the area,
π(r1)^2 + π (r2)^2 = 80π
From the statement, we know that r2=2(r1).
<span>π(r1)^2 + π (2 x r1)^2 = 80π
</span>We can cancel π, we will have
5 x (r1)^2 = 80
Thus,
r1 = 4 and r2 = 8
Answer:
75 boys
Step-by-step explanation:
Formula-Girls:Boys=Girls:Boys
5:6=_:90
90×5=450
450÷6=75
Distance = rate x time
distance = 60 miles per hour x 7 1/2 hours
distance = 450 miles
Answer:
Option B
Step-by-step explanation:
By applying Pythagoras theorem in the given right triangle,
(Hypotenuse)² = (leg 1)² + (leg 2)²
By substituting the values in the given expression,
7² = x² + 2²
49 = x² + 4
x² = 49 - 4
x² = 45
x = √45
x = 3√5
x = 6.7 ft
Option B will be the correct option.