We know that
the equation of a circle is
(x-h)²+(y-k)²=r²
where
(h,k)-----> is the center
r--------> is the radius
is the center is the point (0,0) and radius r=20
then
(h,k) is (0,0)
(x-0)²+(y-0)²=20²---------> (x)²+(y)²=400
the answer is
the option D.) x2 + y2 = 400
15:20
divide each by 5
3:4
to find the ratio of the area's we square the ratio's of the sides
3^3 : 4^2
9:16
Choice B
Answer:
x=-4 y=-1
Step-by-step explanation:
Let's solve your system by substitution.
−3x−8y=20;y=5x+19
Rewrite equations:
y=5x+19;−3x−8y=20
Step: Solve y=5x+19for y:
y=5x+19
Step: Substitute5x+19foryin−3x−8y=20:
−3x−8y=20
−3x−8(5x+19)=20
−43x−152=20(Simplify both sides of the equation)
−43x−152+152=20+152(Add 152 to both sides)
−43x=172
−43x
−43
=
172
−43
(Divide both sides by -43)
x=−4
Step: Substitute−4forxiny=5x+19:
y=5x+19
y=(5)(−4)+19
y=−1(Simplify both sides of the equation)
Answer:
x=−4 and y=−1
Answer:
The scale factor is 
Step-by-step explanation:
we know that
The scale factor is equal to the ratio between the side length of the scale drawing to the corresponding side length in the actual
so
