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:
64.81
Step-by-step explanation:
x + .08x = 875
1.08x = 875
x = 810.19 (price of tv)
810.19 x .08 = 64.81
Answer:
since Sonia saved 45$ in 5 weeks and 70$ in 10 weeks. we are to find the amount she saved up in x weeks.
let's make the amount y
so x= y
5 = 45 cross multiplying the values
we then have 45x= 5y
y= 7x
x=y
10=70
10x = 70y
y= 7x = y=5x+ 20, y = 20x+5
Answer:
3(c+4)
Step-by-step explanation:
It would usually be 3 x 4, but since there is a variable, it can`t be multiplied (unless you know what the value of the variable is). Thus the expression is 3(c+4).
